G has a "swell" time kayaking

G has a "swell" time kayaking
G has a "swell" time on Lake Michigan in an inflatable canoe

Dawn on the Gulf of Mexico

Dawn on the Gulf of Mexico
Dawn on the Gulf of Mexico

Warren Dunes Sunset

Warren Dunes Sunset
Warren Dunes Sunset

Tuesday, November 5, 2019

Coach Batteries - How to get the most out of them

DC Voltmeter and Ammeter to monitor the coach batteries.
I added this to improve upon the Roadtrek LED battery indicator.

If left on, it also provides a power reading and energy consumed.
Roadtrek L-F-G-C battery display -
4 LEDs lit indicates charging or fully charged.

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The post points out what I've learned  about my AGM batteries including limitations of the L-F-G-C  battery display which is simple to read but can be misleading, as I discovered.

How do we use the Roadtrek if we're not in a campground? This is important because it influenced our battery decision. We do overnight in the Roadtrek off of the grid, but we don't do a lot of boondocking. If the temperatures are above freezing but cold we may run the generator and the heat pump. However, G and I have also slept in the Roadtrek in sub-freezing temperatures while off the grid and below the limit for the heat pump. We will then run the propane furnace if necessary and that requires 12VDC.  If temperatures dip into mild sub-freezing overnight and we haven't winterized we will run the hot water heater on propane and the furnace. If we are on propane I don't think it is practical to run the generator continuously overnight and we usually don't. We rely on battery power.

What I discovered. I did not understand the limitations of that L-F-G-C Battery indicator and learned that "F" or "Fair" is really "Poor" because the batteries may be nearing depletion at that point.

I also learned that the Inverter Off-On switch didn't always turn off the inverter function of the Tripp Lite inverter/charger; that was a switch malfunction. It caused unexpected battery depletion.

I realized I had been mis-using my batteries. I didn't understand that the entire 220Ah or rated battery capacity is not available unless I want to seriously reduce the lifespan of the batteries. I also learned that repeatedly using the batteries below the "F" Fair indicator and until only the "L" or "Low" indicator was the only one illuminated was not good for the batteries, if I want longer battery life. My lack of understanding coupled with an inverter switch problem led to the early demise of my first set of AGM batteries.

I've learned about AGM batteries and when I replaced them I also investigated Lithium-Ion batteries (LiFePO4). I'll point out what I discovered about the AGM batteries in this post, but first, I decided that I would continue with AGMs because:

  • 220Ah AGMs are sufficient for my use (approximately 110Ah to 170Ah useable - explained in this post).
  • I have an Onan generator which I can use to provide power for coach appliances and charging.
  • I was concerned about the low temperature charging restrictions of LiFePo4 batteries because my AGMs are mounted outside in the rear of the coach. That is the location I would use for LiFePO4 replacements.
  • I did not want to open my wallet for the more costly LiFePO4 batteries.
  • I decided to add a small 50W portable solar panel with de-sulfating 180W controller to help charging of the batteries. I concluded this was a better use of my money as compared to the LiFePO4 batteries. I may eventually put a 100W panel on the roof.
  • I decided that adding a good DC voltmeter/ammeter to monitor the batteries would assist me in using them and avoid the earlier problems.
  • There have been improvements in technology, and who knows, I may change my mind in 2-5 years.
This post is about a few things that may help you improve the life of your AGM batteries. 
I include a typical 12VDC energy audit at the end of this post.

My 2013 210P Roadtrek has two 6-Volt AGM lead-acid sealed batteries rated 220Ah. I use these on our treks in both warm and cold weather. We don't boondock a lot, but we do spend overnights off the grid. The numbers in this post are with those batteries in mind.

Some things I have learned
These lead-acid batteries can provide 4-6 years of good life, and sometimes more. But how they are used is a significant factor and determines how long they provide good service. Here are a few things to be aware of, and more on what the indicator in the Roadtrek is attempting to display and how it relates to what we observe with our batteries.

I don't think it is possible to reverse the aging of these batteries. It is possible to damage them.

How the batteries are used and discharged/charged is probably the single greatest determinant of how long these lead-acid batteries can provide good service. Battery life is determined by age and these cycles. We sometimes don’t get the life out of the batteries we may expect. I have two 6-volt AGM batteries. They are wired in series to provide 12V DC and can provide a maximum of about 220Ah (Ampere-hours).

What are DC Watts and Volts and Amperes?
These are important because they relate directly to our batteries. If we know the amperes our appliances and lighting are using we can estimate how long on a charge we can run them.

You can skip this and move on to the next section, but I think you will want to read this before you do an audit of your DC appliances and get a better idea of how much battery power you are using.
  1. Watts are Volts multiplied by Amperes. In our Roadtreks with 12V AGM batteries:
  • 12V x Amperes = Watts; for example 12V x 5A = 60 Watts.
The battery voltage does stray but for doing calculations using 12V is handy.
  1. Because we know watts and the voltage, we can calculate Amperes. For example:
  • Watts divided by volts = amperes. A 100 watt DC appliance: 100W/12V = 8.33A
An Ampere-hour (Ah) is a measure of amperes used per hour. Batteries are rated in Ampere-hours.
  • An Ampere-hour is using one ampere continuously for an hour: 1A x 1 hour = 1 Ah
Ampere-hours let us determine how much battery capacity is being used. For example, let's assume we three things that are using DC electricity:
  • 1.0A lights
  • 0.8A charging phone
  • 2.6A furnace and fan.
If we add these up, we can see how many Ampere-hours they would use in one hour:
  • 1.0 + 0.8 + 2.6 = 4.4A
  • 4.4A x 1 hour = 4.4Ah
If we multiply by the number of hours these appliances and lights are "on" we can determine how many Ah will be used in total, and as you will see this is useful for estimating how long our batteries will provide us with electricity between charges.

For example, let's say we left those appliances and lights on overnight, for 8 hours. Here is how much battery capacity they would use:
  • 4.4A x 8 hours = 35.2 Ah
Later in this post I provide some estimates which can be used to determine how long your batteries could last when providing DC power.

What use is knowing Ampere-hours? Ampere-hour (Ah) rating of a battery is a measure of how many amperes a battery can provide when discharging. One Ampere-hour is one ampere for one hour.

Unfortunately, a battery rated 220 Ah cannot provide 220 Amperes continuously for one hour.  In watts that is 220 A x 12V = 2640 Watts total.

A 220 Ah AGM battery cannot be used that way.  The more we attempt to pull from our batteries, the less Ah they can provide in a short period of time. I'm using the data provided by the manufacturer of my batteries, which is relative capacity. Relative capacity takes into account "battery fade" which normally occur to batteries as they age and are used:
  1. To get good battery life, these batteries should not be repeatedly discharged more than about 50%, and when discharged should be immediately recharged. In other words, one cannot get 220Ah out of these batteries if we want good life from them.
  2. A 50% discharge of 220Ah is 110Ah that we can use. The batteries must then be recharged. AGM batteries discharged repeatedly 50% and then recharged can provide about 1200 charge-discharge cycles. That’s the service life. Keeping batteries fully charged and not storing them partially discharged also is an aid to improved service life. Temperature also impacts service life, and temperatures above 77F reduce battery life.
  3. These batteries can be discharged repeatedly by 80% but that will reduce the life. A 80% discharge of 220Ah is 176Ah that we can use. AGM batteries repeatedly discharged 80% can provide 700 charge-discharge cycles. That is much lower than the number of cycles if we only discharge to 50%.
  4. Many battery manufacturers use a 20 hour rating for batteries. That is a more realistic and useful measure of battery capacity. For example, my AGM batteries are rated 220Ah, which implies continuous 220A for one hour. The actual 1-hour rating of the batteries is only 130A.
  5. The battery can, however provide a total of 220Ah over 20 hours of discharge.  That is a continuous 11 amperes for 20 hours.  But we should only go for 50% which is 5.5 A for 20 hours. This is to get better battery life. 
  6. Over 10 hours, a typical night, the battery can provide a total of 210Ah according to my battery manufacturer. In other words it can provide 210Ah/ 10 hours = 21 amperes continuously each hour for that 10 hours. But, if we only discharge the battery 50%, of the 220Ah full rating, that implies about 110Ah/ 10 hours or only 11.0 amperes continuous discharge for 10 hours.

    Conclusion: Over a typical night, my batteries could provide 11.0 Amperes each hour and provide good service life.
  7. These are the characteristics of the batteries in my Roadtrek when they were new. This capacity diminishes with battery age and use. 
  8. There are differences between manufacturers, so it is best to check the specifications for your batteries.
What are cycles?
  1. What does 1200 charge-discharge cycles mean? That's the number of times we can discharge and immediately recharge the batteries. For example, if you discharged the batteries to 50% and then fully recharged them once a day and every day, they could have a useable lifespan of 1200 days. 1200 days/365 days per year= 3.2 years battery life.
  2. If you did this every three days, then we would complete a cycle every three days, or 365/3 days = 122 cycles in a year.  1200 cycles/122 cycles per year = 9.8 years life.
  3. However, because of other factors including temperature, length of time the batteries sit in a partially discharged state, battery age, etc. it is unlikely we will ever achieve this in our Roadtreks.  The manufacturer’s battery data is based upon ideal situations, including a temperature of 77F
What occurs as batteries age? As batteries age there are internal changes and that reduces the capacity. For example, after 600 cycles of charging and discharging the battery to 50% what occurs?
  1. As the batteries age, even under ideal conditions, we may not get that 110Ah because the capacity of the battery diminishes as it ages. This is called battery fade. In other words the battery initially can provide 220Ah, but the actual capacity decreases over time.  We notice this as a more rapidly falling terminal voltage, which we can see on the Roadtrek L-F-G-C display, which spends less time in the “Good" area. In other words, the display falls from C to G to F more rapidly than one would expect. That is an indicator of aging batteries with diminished capacity. Eventually we decide that the batteries don’t provide us with enough power to get through the night or whatever while powering our devices. We then get new batteries.
What happens if we repeatedly discharge the batteries below 50%?
  1. Frequently discharging the batteries below 50% will further reduce the service life. For example, we can repeatedly discharge them to 80% (20% remaining). If we do this,  the service life will decrease. My battery manufacturer states that discharging repeatedly 80% will reduce battery life to about 700 cycles. That is considered to be the lowest acceptable service life.
  2. At 700 cycles if we discharge and charge every 3 days (122 times a year), the batteries will have a useful life of about 700 cycles/122 cycles per year = 5.7 years. But we must also consider the aging of the battery, temperature and so on. These also reduce battery life.

There is a trade-off.
  1. We must decide between longer battery life, or more power from each charge, or a compromise. In practical terms we must choose between how long we want to power our DC appliances each time we discharge the batteries and how long a battery service life we want. We can’t get both maximum power for maximum time because the deeper we repeatedly discharge the batteries the shorter the service life. We notice this as how quickly the available power diminishes. Of course, we can replace the batteries every three years or so. That is a financial decision.

Does the Roadtrek “L-F-G-C” tell me when the battery is at 50%? The information I have about this is the “G” indicator is “ON” if the battery in my coach is above 11.9 volts, which is about 29% state of charge for my batteries.
  1. If I use the "G" indicator and recharge the batteries when it goes out, then my battery manufacturer indicates that I can get about 800 cycles from my batteries if I discharge them to about 20-30% repeatedly.
  2. Important Note: I have not verified the Roadtrek indicator with actual measurements comparing the battery voltage to the indicator LED thresholds (I use a voltmeter and no longer pay much attention to the indicator). I'm using published information and it is my understanding that the “F” indicator is “ON” if the battery is above 11.2V,  but the table for my batteries indicates a 0% Relative state of charge when the voltage decreases to 11.6V and completely depleted at 10.5 volts. The table provided by the manufacturer of the AGMs in my Roadtrek indicates 50% relative State of Charge = 12.35V and 100% State of Charge = 12.9 volts.  I’ve seen other AGM charts and those batteries were in the range of 11.66V (20%) to 12.05V (50%) to 13.0V (100%).
What else should I know about the Roadtrek “L-F-G-C” indicator?
  1. It measures battery voltage. This is an approximate indicator. A battery will give two different voltage readings. One reading if it is being discharged; the another is if it has rested (no discharge) for about 6 hours.  The battery specification for “State of Charge” are usually for a resting battery. If a battery is discharged and then allowed to rest the voltage will usually increase. In other words, the battery may have more capacity remaining than the “L-F-G-C” indicator represents when we are in our Roadtrek and discharging the coach batteries.
What is the best approach for the batteries?
  1. Use a voltmeter if we want a better idea of the condition of the batteries, so we avoid excessively discharging them. Avoid high temperatures because battery life decreases at higher temperatures.  Measured  life is usually at 77F and many batteries will lose half of their life if the temperature is 95F. Don’t charge if above 120F. Charge the batteries after every period of use. Don’t discharge more than 50%. All of these things improve the life of the batteries.
  2. We can add a voltmeter in the rear cabinet of a 210P to monitor the voltage. 
  3. 12VDC socket in the rear of my 210P

    Inexpensive 12VDC digital meter
    plugs into socket in photo above
    Inexpensive 10 inch Splitter Cable for 12VDC
    Use if we need two devices from a single 12VDC source,
    such as the photo of the cabinet, above. 

    Dual, fused splitter with digital voltmeter
    and USB sockets

    As battery capacity diminishes what does that mean in practical terms if I want to boondock? 
    1. There is a trade-off. Longer battery life, or obtaining more power from each charge. This is further complicated because as the batteries age, their capacity is diminished. The actual capacity of a 200Ah battery will gradually decrease to 190 Ah, 180 Ah, 170 Ah and so on. This is because the internals of the battery change as it ages. We usually notice this change because the voltage decreases more rapidly as the battery discharges. 
    2. The beginning voltage of a fully charged battery will be that of the charger which is about 14.7 volts, this is called “surface charge” and this charge dissipates quickly as we discharge the battery. Both good and faded batteries will usually show a "C" when on the charger, and immediately after they are disconnected.  That is deceiving and is not indicative of the actual state of the batteries.
    3. If an older 220Ah battery has a capacity that begins at 160Ah capacity then it won’t take very long to get to that 110Ah level which is the 50% capacity level of the new battery. We see this as a more rapid movement of the indicator as the indicator moves more rapidly from “C” to “G” to “F”.

Are there other things I should be aware of?
  1.  Here is the short list. Batteries must be properly charged in accordance with the manufacturer’s instructions, automatic chargers are best. For golf cart batteries at 12V that usually means an Absorptive/bulk charge at 14.7 volts and a Float charge at 13.5 Volts. AGM batteries may be slightly different with an Absorptive/bulk charge at 14.4 volts and a Float charge at 13.5 Volts. My AGMs recommend an Absorptive/bulk charge range of 14.4-14.7V and a Float charge of 13.2-13.8V. Because the lead-acid batteries are chemical devices, there are other noticeable issues. 
  2. Battery capacity is reduced at lower temperatures. A 200Ah AGM battery may have a capacity of only about 80% at 32F or 160Ah.  However, that is at a discharge of about 20Ah (about 4A per hour for 5 hours).If we increase the to 40Ah, the capacity reduces to about 70% or 140Ah. (That provides a rate of about 8A per hour for 5 hours). However, we still have to watch the battery voltage to determine the actual condition, or state of charge. We can’t simply watch a clock.
  3. A 200Ah AGM battery is rated to provide that amount, 200Ah over 20 hours. It can provide 200Ah/20 hours = 10 amperes per hour continuously for 20 hours. But we would not want to exceed that 50% discharge limit if we want acceptable battery life.  In practical terms, a 200Ah battery should be considered 100Ah. if that is so, it can provide 100Ah/20 hours = 5 amperes per hour continuously for 20 hours.
  4. If we increase the amperes used, then the time the battery can produce it will decrease. The same batteries will provide only about 170Ah over 5 hours, not the 200Ah rated over 20 hours. In other words, the more power we demand, the total amount decreases. That’s because these are chemical devices. If the batteries could provide 170Ah over 5 hours, that’s 170/5 or 34 amperes each hour at 100%. But if we allow only 50% discharge, we then can use only 34A x0.5 = 17 amperes per hour over the 5 hours. 17 amperes x 12 volts = 204 watts connected to the battery. 
  5.  If we use an inverter to get 120VAC from our batteries, we need to take into account the inefficiency of the inverter. In other words, if we run a 200W appliance at 120VAC on the inverter, the amount of DC power going into the inverter is greater than the AC power coming out. Simply turning on the inverter uses power, perhaps as much as 200W. To maximize battery power, leave the inverter Off if we don't need AC from the batteries.  Tripp Lite suggests using 1.2 as an inefficiency multiplier:
  • Begin with the AC amperes or watts of the 120V appliance. If 2.5A, then the watts are 120V x 2.5A = 300W.
  • Then to determine DC amperes divide by 12V.  300W/12V = 25 DC Amperes.
  • To estimate the battery Ampere-hours (Ah) required, multiply the DC Amperes x time x inefficiency.  25A x 4 hours x 1.2 =  120Ah. That’s a rough estimate and it exceeds the 50% capacity of a 200Ah battery.
  • To determine amperes from an appliance using DC watts (such as a TV), simply divide the watts by 12 volts.  For example for 100 watts: 100W/12V = 8.33 A
How can I recharge my batteries? The sources of electrical energy for recharging are determined by what’s installed in your Roadtrek. These may include the following:
  • Vehicle engine.
  • Shore power.
  • Onan generator.
  • Underhood generator (GRU) - I don't have this.
  • Solar panel.
How long does it take to re-charge batteries?
The more depleted the batteries, the longer the charging time required. 

  • Using 120VAC and the Tripp Lite 750 Watt Power-Verter DC-to-AC Inverter/Charger, it can take 12 hours to completely recharge discharged coach batteries. This was confirmed by a factory technician. Furthermore, the charger has two settings: 10A and 45A.
  • Using the Onan generator is the same as shore power because the Tripp Lite is used.
  • Solar may take longer. This is determined by the amperes available from the solar panels. If a 45A Tripp Lite requires up to 12 hours, it is reasonable to assume solar may require more time because a 200W solar panel is providing about 17A. However, most RVs on solar don't draw down the batteries because during daylight hours the solar provides a part or all of the DC power requirements of the RV.
I need a 12V DC power budget.  To do this we need to do an energy audit. That’s a way to determine how far my batteries can go before I run out of DC power, and then have to recharge
  1. To get maximum power available and maximize your batteries, it is better to use 12VDC appliances than 120VAC connected to the inverter because of the inverter losses. 
  2. Add up the DC amperes to determine how much you use. Then calculate the Ampere hours to see how long your batteries will last before requiring a recharge.
  3. Add up the ampere requirements of all of the DC appliances and things in your RV. Product labels are reliable sources. Because there are differing options, I can't provide the Amperes required for each and every device. But I do provide a list with some approximations if I know what they are:
  • Lighting 12VDC (LED uses less DC energy than bulbs and fluorescent) - Varies.
  • Each LED light may require 0.25A.
  • Lighting 12VDC fluorescent, single 20W bulb - 1.3 to 1.8A. 
  • Lighting 12VDC fluorescent, dual 20W bulbs - 1.8 to 2.2A. 
  • Propane detector 12VDC about 0.1A.
  • 12VDC TV (about 32W or 2.7A).
  • Amplified TV antenna - varies.Macerator 17A 12VDC when running.
  • Water pump (varies with pressure and flow, possibly 5A 12VDC when running).
  • Inverter 2A losses or more if ON.
  • Roof fan - Fantastic Fan 3350 - 2.5A when running (varies with speed).
  • Bathroom fan.
  • 3-way Refrigerator 12VDC for controls - approximately 1 to 2A.
  • 3-way Refrigerator on 12VDC cooling - approximately 20A.
  • Dometic LCD single zone thermostat.
  • 16,000 BTU Suburban Propane Furnace when running - 2.8A.
  • 12,000 BTU Suburban Propane water heater - 12VDC Module board - 1.0A.
  • 15 inch Laptop - estimated 90 watts 120 VAC.
  • Smartphone charging - estimated 5 Watts @120V,  0.5A @ 12VDC.
  • CPAP machine - varies.

(c) Copyright 2019 Norman Retzke "All Rights Reserved".  See disclaimer notices.

Wednesday, October 30, 2019

Coach Batteries - AGM versus Lithium Ion Update

AGM Lead Acid batteries in my 210P. Mounted outside. 

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Here's an update on lead acid sealed AGM batteries versus Lithium Ion (LiFePo4) as coach batteries in my Roadtrek. If you have a Chevy based Roadtrek, you probably have two 6-Volt 220Ah AGM batteries as I do.

Note: 1. I'll post an article about what we can expect from our batteries and my experience powering the stuff in my Roadtrek with AGM batteries since December 2013.

When we compare batteries, we usually look at these three types:
  1. 6V type GC2 golf cart batteries. These lead-acid batteries, are not sealed, and do require addition of distilled water from time to time. They also do vent gasses.
  2. 6 V type AGC2 AGM batteries. These are also lead-acid batteries, but they are sealed and require no maintenance.
  3. 12V LiFePO4 Lithium-Ion batteries. These are radically different than the golf cart and AGM batteries. 
So which is the best type? That requires considering the trade-offs which depends upon your use, and how much money you are willing to spend, and warranties.  Our 210P has an Onan generator and I added limited solar too.  If we are not on shore power we need battery power to get through the night, and then we recharge. If battery power is low we can run the Onan generator, or the chassis engine. We use the inverter sparingly to give us 120VAC. So we don't need a lot of battery power. We also have propane for the stove top and for the hot water heater. Your situation might be different.

Trick question: Should one invest in LiFePo4 batteries or in Solar Panels?  I won't attempt to answer that in this post.  The answer lies in how much electrical power do you need to get through the night, when batteries are important, or use a generator.

In fact the real issue is making a useful comparison of electrical energy sources when off the grid. These include batteries, my Onan generator, and my solar panels.   This is a somewhat unequal comparison, because my Onan can provide 2,800 watts of continuous power. That's sufficient to run my Air Conditioner and the Onan consumes about 25 ounces of gasoline per hour at low power and 55 ounces per hour at full power.

My point is, we are comparing energy sources, and the costs of those sources.  This post will not compare the cost of solar panels and batteries to other sources.

Here is a quick comparison of batteries. I use Battle Born Battery as the Lithium-ion comparison because they seem to be a well made battery with a "10 year warranty".  These would also work with the TrippLite inverter charger in my Roadtrek, with a change in settings to "Gel", because according to Battle Born "the battery prefers to bulk charge at 14.4 volts and float at 13.6 volts".
  1. GC2 and AGM batteries are both lead-acid batteries. One of the characteristics of these batteries is they should not be repeatedly discharged below 50% to get maximum life.  So, my 220 Ah batteries can only really provide about 110 Ah of electrical energy if I want to get maximum life from my batteries. 
  2. LiFePO4 type Lithium-ion batteries are radically different technology. So they are significantly lighter in weight than any lead-acid battery of similar capacity. They can be repeatedly discharged 75 to 80% without decreasing the life of the battery. They also can tolerate more charge-discharge cycles than the lead acid batteries. A 200Ah LiFePO4 battery can provide 160 Ah of useful electrical energy. 
So why haven't we all switched to Lithium-ion batteries? It is because even if we consider the advantages, the lithium batteries also have some disadvantages.

  1. LiFePO4 batteries cannot be charged if they are below freezing temperatures.
  2. LiFePO4 batteries are significantly more expensive than AGM batteries.

Here are some cost comparisons. I'm going to use two different AGM batteries and compare them to a "drop-in" Lithium-Ion battery replacement made by Battle Born Battery company:

  1. Amstron AP-GC2 6V AGM Deep Cycle Battery. This is rated 210 AH and is currently available for $209.99 at atbatt.com. List at $299.99. Two required to achieve 12V at list = $599.98.
  2. Deka 8AGC2 (8AGC2M) 6V Deep Cycle battery. Made in USA. This is rated 220 Ah and is currently available for $389.70 via Amazon. Two required to achieve 12V = $779.40.
  3. Battle Born 12V 100 Ah "drop-in" battery list $949 each. Two would provide 160 Ah of electrical energy versus 110 Ah for lead acid.  This is considering a 80% discharge versus 50%  discharge, which are the recommended maximums for these batteries. Price per battery $949 or $1,898 for two, which is required to achieve 200 Ah.  However, if you are an Escapees RV Club member, you can currently get a 15% discount.

So what are the issues? A couple of years ago, I looked at the replacement of my two 6-V AGM batteries with Lithium Ion batteries.  These were the issues I considered then:

  1. Available power. The Lithium-ion batteries can provide more electrical energy and more discharge-charge cycles.  My AGM batteries can provide 110 Ah of useful electricity while Lithium-Ion which occupies the same space can provide 160 Ah. This is not trivial if one wants to boondock and could be an incentive to consider Lithium-Ion batteries.   
  2. Temperature Restrictions. When I evaluated Lithium-Ion batteries a couple of years ago, I discovered that they should not be charged if the battery temperature is below freezing 32F (0 C).  My 210P carries the batteries in an outside compartment. Because we do trek when it is below freezing, that was a serious impediment. The Battle Born batteries have a low temperature charging limit of 25F.  The batteries are prevented from charging below 25F. However, they can continue to discharge until they reach a "low voltage limit" which is below 10 volts. 
  3. Alternative Location. I even considered moving the Lithium-ion batteries inside of the coach as a means to get them above freezing, but that would displace useful space and add to the installation cost.
  4. Cost. Comparing the Deka AGM to the Battle Born the difference is about $1,118. Comparing the Armston the difference is $1,199.96.
  5. Weight. The Battle Born batteries are about one-half the weight of the AGM batteries. If weight is an issues, that reduction of about 60 lbs could be a significant factor. 
  6. Warranty. Most AGM batteries can be expected to have a life of 5 years, or more. Some Lithium-Ion battery manufacturers offer a 10-year warranty. That means that one set of Lithium batteries is the equivalent of two sets of AGM batteries.  This should be considered when evaluating batteries. 
  7. Temperature and voltage affects - AGM. AGM battery specifications are under "ideal" conditions. These include an ambient temperature of about 77F, discharging to no more than 50% and then immediately recharging.  That may not happen in the real world. AGM batteries do experience reduced capacity in cold weather. AGM battery life will also be reduced at higher temperatures. In other words, that 110 Ah available will decrease as the ambient temperature decreases and may be 25% less at 32F and 20 A discharge rate.  Under high discharge rates the capacity is further reduced. There is a lot of data about AGM and other lead acid batteries because there are so many manufacturers and they have been in use for many decades. 
  8. Temperature and voltage affects - Lithium ion batteries. Using Battle Born Battery data for their "drop-in" 100 Ah battery, they state that the "Output voltage is flat during most of the discharge cycle". Furthermore can provide "100 Amp Continuous Current".  The company states that the batteries have low and high automatic temperature protection which shuts down the battery if temperature falls to 25F or a high temperature of 135F is reached. 
  9. Lifespan. The AGMs in my Roadtrek are designed for about 1200 charge/discharge cycles if they are not discharged below 50%. According to Battle Born the lithium ion batteries "Approximately 75-80% of the battery capacity will remain after 3000 cycles in applications recharging at 0.5C or lower". The recharge "C" rating for a 200Ah battery is 0.5 x 200 A, or a charging rate of 100A. The lithium ion batteries will have much more life remaining than the AGMs after a couple of years of normal use. My AGMs should give good service for about 5 years, or longer. The Battle Born batteries will exceed that. 
  10.  "Useful Life". Lead-acid batteries experience a reduction in capacity as they are charged and discharged because of internal changes, primarily sulfation. This reduction can be significant. After a year of use, my AGMs experienced about a 10% reduction. So, my useful 110 Ah decreased to about 99 Ah. Since then my batteries have leveled out, based upon voltage after a moderate period of discharge. The lithium ion batteries retain their capacity for a longer period of time. That can be important if one needs every bit of electricity available in the batteries when new. 
When I looked into replacing my AGM lead acid batteries with Lithium-ion, I also considered space requirements:
  1. Inside LiFePo4. I would have to give up some under the bed space, because the Lithium Ion batteries should not be charged if below freezing. In fact, the Battle Born battery internal battery management system prevents charging below 25F.
  2. Inside AGM. If I kept my two outside AGM batteries and added two inside, that would provide me with 220 AH of energy versus 160 Ah for the Lithium Ion batteries. In other words, I'd get about 38% more energy from four 6-V AGM batteries. However, those four batteries would weigh about 272 pounds. Two Battle Born batteries would weigh about 62 pounds. 
  3. Inside AGM and Battle Born comparison. The above with four AGM batteries provides about 220 Ah at the best case at 272 pounds. If I added one Lithium Ion battery to total of three, that would increase the energy available to about 240 Ah. The weight would be about 93 pounds. 

The show stopper:
When I considered AGM versus Lithium-ion, I had these issues and yours might be different:
  1. I wasn't willing to mount the LiFePO4 batteries inside the coach, because I didn't want to give up that space. That would be to keep the batteries above 25F while cold weather trekking. 
  2. If I compare the normal life of AGMs (5 years or so) to the Battle Born LiFePo4 (10 year warranty) this changes the costs. To get 10 years of use from AGM batteries would probably require replacement after 5 years. In 10 years the two changes of AGMs is $779.40 each, for a total cost of $1,558.80 for Deka versus $1,878 for Battle Born. 
  3. If I needed more overnight DC power, the Battle Born could be worth that extra $319. After all, considering the 10 year "warranty" life of the batteries, that's only about $32 per year. 

For more about Battle Born Lithium Batteries:


Copyright (C) 2019 Norman Retzke, "All Rights Reserved"

Original material:  https://roadtrek210.blogspot.com/

Tuesday, October 22, 2019

Cool and Cold Weather Trekking

A Snowman in New Orleans, Louisiana
Complete with hard hat and safety vest

Early morning in 19 ft. All-electric Sprinter after an 18F night.
G is making oatmeal with water heated on the electric cooktop,
Our first Trek, no microwave, just an electric cooktop, no furnace either
Just a small electric heater  - a real camping experience,
we have made some changes since then!

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Hint: Click on images to enlarge them.....

If you want to winter RV, well here is a possible vehicle,
 built on a PistenBully Snowtrak (Peterson Equipment Co).

We don't always plan to do winter camping - Winter Happens!
Winter happens, even in New Orleans LA there is sub freezing weather and snow, from time to time.  I've also encountered this in Charleston, SC. too, and so on. I've experienced snow in July, too. When trekking in the late fall or winter, it is quite likely we will encounter sub freezing weather for a day or a few days.

This post is about our experiences in cool to cold weather trekking and how we did it. We choose to be comfortable in the winter and we hope this post will provide you with some ideas, and that your winter treks are both fun and comfortable.

Some of our modifications accommodate hot weather trekking, too.  We may not plan on living in our Class B Roadtrek in below freezing weather, but we will travel with it in freezing weather and we have spent a few days in nighttime temperatures as low as 5 F.

I am not advocating living in a Roadtrek in continuous below freezing temperatures. There are practical issues to deal with, and this post points out some of them. I am writing that trekking comfortably in freezing conditions is possible.  Living in our Roadtrek 210P in sub freezing temperatures even for a few days has been a challenge. Open the door and that snow, sleet and cold enters our living domain.   Having plentiful hot and cold running water is a dream. However, we will and do encounter below freezing temperatures while trekking and our 210P has kept us comfortable. This post is about that kind of trekking, going from place to place and in the process encountering cold weather, and dealing with it in comfort. For example, our longest trek was 110 days, but we only encountered cold weather for a few of those. That was a combination of choice, and flexibility. We can and do escape the majority of the cold weather. "Have Roadtrek will Travel" LOL.

Read on to see how we deal with the limitations. I also point out that some of the things we do are advantageous to improved comfort during hot weather trekking. This is so because the issue we are dealing with is the outside temperature, both high and low, and extremes will impact our interior comfort.  Some methods to deal with those outside temperature extremes are equally effective in both hot and cold weather. Of course, in hot weather we aren't concerned with freezing water systems.

Our first trek in our 210P put us into winter conditions because we simply couldn't escape to warmer weather fast enough. That's the reality when one treks in late fall or early winter. Weather has a way of intruding. Fortunately for me I've done a lot of winter tent camping. G on the other hand really loves the snow but wants to hunker down in front of a fireplace as soon as possible.

We've taken what we think is a realistic approach to our desires in trekking via our Roadtrek. If we travel in the early spring, the fall or early winter we should expect to encounter cold conditions. So it is best to prepare for it.  It's again that time of year and we are thinking of trekking and keeping comfortable in our Class B RV as the outside temperatures decrease. We are prepared. When trekking in winter conditions we do carry hats, hoodies, winter coats, scarf, gloves, warm socks and boots.  I even have a balaclava. This is as much as a preparation for breakdowns as for anything else.

Each year we encounter sub freezing weather. We have trekked and overnighted down to 5 F in our 2013 210P. That winter night was not planned, but we had prepared. Our 210P has kept us comfortable, but there were some things we had to figure out, and some things we did to improve the winter conditioning of the 210P. This included enhancements to active and passive temperature controls.

Our first cold weather experience was six years ago in a rental Class B in some of the National Parks in Utah. When nighttime fell below 20F, we had some difficulty keeping comfortable. Our only source of heat was a small electric heater, and we didn't have sleeping bags; just a down blanket. We learned from that experience and modified our approach. The 210P was a vital step in that. We have yet to use sleeping bags, because in our 210P they aren't necessary for us.

Winter at about 7500 ft elevation - " a real snot freezer"
June Morning
Walking at 10,600 feet elevation, in June

Comfort Factors
Temperature based comfort in a class B (or any RV, for that matter) is determined by a variety of factors. Comfort includes:
  • What we wear (dry clothing preferred),
  • Type of undergarments (wicking is better),
  • What we eat (warm foods, liquids and carbs in cool weather); good food makes winter weather far more enjoyable,
  • The amount of activity (more is better in cold weather),
  • The insulation in the RV (to assist in keeping interior temperatures moderate and reduce heat loss) in winter, and reduce heat gain in summer,
  • The amount of moisture in the air inside the RV (too much results in condensation in the winter, too much in summer is simply "sticky"),
  • The ventilation in our RV (to keep interior moisture under control). 
  • The energy sources available (for both heat and cooling),
  • Floor construction and carpeting.
  • Where we park. In daylight, that sunlight can help heat the RV. However, at night there is no solar heat available. In hot weather, we prefer the shade.
Furthermore, comfort is relative and subjective. Under high activity conditions in cold weather we are not nearly as susceptible to the environment as we are during periods of low activity. Burning calories releases heat, warms our muscles and improves our attitude.  The converse may be true in hot and humid weather conditions.  However, the focus of this post is cool to cold weather.

There was a time when they called Class Bs "Camper Vans" with limited amenities. Today some are being promoted at "Glamper Vans" and some include heated floors, etc. but there is still the weather to deal with. Open the door on your Glamper Van and you will get a dose of the winter reality you are travelling in.

My "Other" Camping Experience
Prior to roadtrekking I was a backpacker and ground camper. We camped for short periods in winter weather and I was trained and learned enough to be proficient at doing it and to pass what I learned to others.  Skill and technique really does make a difference. The lowest temperatures I experienced with such camping was -25F (-32C). That was definitely a challenge, because our only source of heat was a campfire! In my opinion the most comfortable winter camping was at about 10 to 15F (-10C) . At those temperatures humidity was low, air temperature was not in the "frigid" range, simple steps avoided frostbite and our warming campfires were adequate.  We could and did cook outdoors under those conditions. Of course we slept in sleeping bags. However, this post is not about that.

Our first cold weather trek - a learning experience
Cold weather is determined by geographical location and altitude.  When trekking we are changing both and at the higher altitudes we do encounter cooler weather. Of course there is the dreaded "Arctic Vortex" whatever that is.

Our first cold weather trek was not in our Roadtrek. It was in a rental Class B. This was an all-electric coach with a two burner electric stovetop. It had no propane,  no microwave and no furnace. Interior heat was from a small portable electric heater, or running the engine. We were pretty much dependent upon that 120VAC 30 ampere electrical connection and solar panels. That was an October experience in Utah at National Parks with temperature dipping below 20F at night. We learned a lot from that experience and it did require that G wear mittens inside. The trek was a wonderful experience, but I decided I wanted multiple energy sources in my Class B. G simply wanted more comfort. We used that experience to make a list of what we wanted and what we would do differently.

Heat, cooling and cooking is determined by Energy Sources Available.

Our second winter trek, in a multi-energy sourced Roadtrek
Our second trek, in the first week of December 2013 was interrupted by winter. That was not the plan, but our departure was delayed. This was to be our "shakedown" cruise in our newly purchased 210P. We were headed to Florida a week after purchase, but had to deal with the consequences of a sudden cold weather front. Yes, these things do happen when travelling from the Midwest to the South. It was a comfortable experience, but additional modifications, many simple,  have since made our trekking even more comfortable.

First winter overnight stop in the Roadtrek, kept warm with the generator and the propane furnace.
Getting ready for the morning departure.
Nietzschean Experiences?
We've put all that we've learned to good use. That includes my previous activities as a backpacker and cold weather camping advocate. However, G does not share my enthusiasm for this. So it has been my goal to do things that make our treks in hot and cold weather as comfortable as possible. One measure of my success is the fact that after six years of trekking, G is even more enthusiastic about this. No simple feat if you have arthritis.

The purpose of this blog is to share what we have learned. This post is about cool or cold weather trekking. It is not about winter survival, or living in our Roadtrek through the winter with subfreezing conditions. I assume the reader has a desire to be comfortable hot or cold, rain or shine. I also assume the reader wants to have functional plumbing......

Maintain the chassis and the coach 
It is important that the vehicle be maintained. This is the foundation of all treks and there are two aspects, the chassis and the coach.

We recently completed our 38,000 mile checkup at the Chevy dealer. This included:
  • Change engine oil (full synthetic) and filter, 
  • Check air cleaner,
  • Inspect tires, 
  • Rotate tires and reset TPMS (tire pressure monitoring system),
  • Check brakes,
  • Multi-point lubrication,
  • New windshield wipers,
  • Check and top off all fluids,
  • Check doors,
  • Inspect undercarriage,
  • Verify head lamps, taillights, etc. are functional.
I did my own coach inspections and we did the following:
  • Run hot water heater, inspect anode,
  • Flush and then winterize the water systems (fresh, black, grey),
  • Replace battery separator,
  • Test all interior hinges, latches and replace one,
  • Check coach batteries,
  • Clean entire interior,
  • Check backup camera and monitor,
  • Do monthly run of Onan generator and check oil level (not due for replacement),
  • Top off the propane tank (added 4.4 gallons at Tractor Supply),
  • Run the refrigerator and then clean the empty interior, new baking soda freshener,
  • Run the heat pump and furnace,
  • Run the overhead fan, clean. 
  • Verify Tripp Lite charger and inverter operation, 
  • Test all lamps,
  • New batteries for temperature monitors and CO monitor,
  • New batteries for portable lights
  • New batteries for refrigerator interior fan (an add-on),.
Our well equipped Class B
Our Roadtrek has the following. Some was original equipment and some we added. We use them all:
  • Heat Pump/Air conditioner (good heat to as low as about 40F) - 120VAC,
  • Propane Furnace (as long as there is 12VDC and propane, good to go) - 12VDC and Propane,
  • Ceramic portable heater 750 watt/1500 watt (which we added, and good if there is 120VAC),
  • Water heater - Propane,
  • Reflectix for windows (which we added, keeps heat in and reduces condensation on windows),
  • Circulating fan (which we added, distributes the heat and minimizes cold spots),
  • Electric blanket, dual zone (individual comfort settings, 120VAC)
  • Two-burner stovetop - Propane (we seldom use this),
  • Inductive electrical burner and cast iron skillets, etc. (which we added) - 120 VAC.
  • Screen for passenger side front window (home-made to improve summer ventilation and keep the bugs out. Our Roadtrek has a screen for the side door and one for the rear door. We have not yet used the one for the side door. 
  • Carpeting for the kitchen area. We use a "Quick Drying Memory Foam bath runner 24 x 58 inches". 
Class B Comfort Issues
For one thing, most Class Bs are not well insulated. Our Roadtrek 210P is about R-4.5 according to an email I received in response to my query to Roadtrek. However, single pane glass is about R-0.1 which is just about "nothing" as in "no insulating value". A Class B has a high percentage of glass, compared to the overall surface area of the RV.  That glass creates a constant struggle to maintain comfortable internal temperatures.  Heat escapes from the inside in winter, or comes from the outside to the inside during the summer.

According to the manufacturer, our Roadtrek was designed for 3-1/2 seasons. Well, yes, but one better know what they are doing if they want to trek outside the 3-season envelope and in sub freezing weather. The good thing is, these things can be learned, and a few techniques and modifications can help.

We realized that if we planned to trek comfortably below freezing that we would have to augment the insulation in our Roadtrek. After purchase we have trekked with nighttime temperatures as low as 0 F and daytime highs in the teens. We carry Reflectix cut for every window except the side entry, including the front windshield. We have also done other things to be comfortable in the cold and in the hot.

Reflectix is inexpensive.  I purchased a 50 ft x 48 inch roll. (I use it in three rigs).

Reflectix visible in the Passenger Door Window - cool, dry weather

Reflectix in the front windshield and a sunshade, too (during hot, full sun weather)
Issues - Be aware of conditions and limitations - Do not fight the weather!
Prudence dictates that we avoid really serious weather situations.  We check the weather frequently when cold weather trekking. Not only where we currently are and where we are going. We also check weather patterns that are bearing down on us in 24 hours and longer.  If there is a possibility of really bad weather G and I have an agreement that we will hunker down in a motel; we have yet to do that. In my opinion this is common sense.  We also make reservations when trekking. Of course, one can also hang out in a truck stop if necessary, and we have slept at rest stops and so on. For example, the Ohio Turnpike has limited areas for RVs at some official rest stops, which includes 120VAC 30/50A service for a fee.

I do need to point out that we have had reservations, were delayed en route, called the campground office and were told "No problem, the office will be closed but there will be an envelope with your campsite information on the bulletin board". Upon arrival we retrieved that information and drove to our site, only to find that someone else had taken it.   That can and will happen when weather conditions get ugly. Apparently under those situations those of us who don't plan are willing to hijack a spot in a campground. In our situations, we've been fortunate to find a place to park and we do have a generator. My point is, if you expect your fellow trekkers to keep their agreements, then dream on..... It is a jungle out there.....

Some states have limited capacity to deal with snow and ice. It is prudent to be mindful of that. We've trekked across north Texas at 25 MPH because of poor road conditions.  Something to keep in mind when making those time-to-distance calculations and destination arrival estimates.

We don't fight the weather. We sometimes take a long bypass, or delay our trek so as to avoid serious weather situations, or road conditions that we might not be comfortable in.  Those mountain passes are not fun in bad weather. We also will adjust our plans to accommodate reality.  Our goal is to eventually get to a warmer destination and we maintain our purpose.  When the weather does get "ugly" we stick to interstates or other very major roads. Breakdowns can and do happen and we don't want to be stranded on some seldom travelled two-lane highway going across 50 miles of prairie or whatever. Keep in mind that it is important to be accessible when issues do occur.

My mantra is "icy conditions must be avoided". We've encountered ice and when we do we stop. We have stopped and boondocked when freezing rain began and waited until the sun was up the next morning. After the roads had warmed and thawed did we resume our journey.  Many southern states have minimal snow removal equipment, don't use salt but prefer sand or "nothing". In those areas, people generally wait a day or two for the storms to pass and things to thaw. We do what the locals do.

I'll try to avoid North-South routes that cross what I call the "freeze line".  It is in that area that I've encountered some really poor travel conditions. So we'll head southerly and try to get below that weather line. However, sometimes those situations can go very far south, and they simply can't be avoided.  A few years ago I was driving from New Orleans to Chicago, and a cold front dumped rain in Louisiana and Mississippi was a complete icycle. I slept in a rest stop.  The next morning things were better, but not by much. It was a frozen landscape all the way north.

Here's a spring route we took, to see a few things and avoid some nasty weather:

From Arizona to Michigan and Illinois, via a circuitous, warmer route

Seldom travelled roads might not be the best route in winter weather

Fresh Water and grey and black tank limitations
If one is to winter trek, there are the issues of fresh water and how to deal with wastewater. That includes the black and grey tanks. In my opinion this is the primary limit to cold weather camping in  our Class B. It does not have heated tanks and most piping is not protected or insulated from the cold. If the pipes and tanks freeze expensive damage can be the result. This does severely limit our ability to live "full time" in our 210P in cold weather unless there are other means and sources for fresh water, and a nearby heated toilet and shower.

If it is continually below freezing, the only way to get fresh water into my Roadtrek is to put it into smaller containers, such as a 1-1/2 gallon container in the photo, and store it inside. (More on the interior fresh water tank later in the post). Some campgrounds do provide water to a heated spigot (our experience in Breckenridge CO, for example) but the heat tape stops at the valve, and the whole contraption is in an insulated box. Even if I had an electrically heat traced fresh water hose, my Roadtrek would still freeze. 

Portable Water Container
We Winterize if trekking in below freezing conditions
I am going to be very honest here. The outside fresh water tank will freeze and anything in the grey or black tank in our Roadtrek will freeze at sustained temperatures below 32F (0C).  If the daytime goes well above freezing it will heat the tank contents and they may rise above freezing, but at night the temperature of the contents will fall as the outside ambient temperatures fall.  The contents may freeze. In other words, if both daytime and nighttime temperatures are sub freezing, then the outside fresh water tank, the grey tank, black tank, macerator, dump hose and under-chassis fresh water piping will freeze. Game Over!  The macerator cannot pump chunks of ice......

If we are trekking in sub freezing conditions, we winterize our 210P.  The inside fresh water tank can be used "in mild freezing conditions" according to my Roadtrek manual. However, there are restrictions. We do not use fresh water in the interior tank in the winter. We winterize the entire water system and carry portable containers of water. We add antifreeze to the gray and black tanks and use the sinks and toilet sparingly.  I carry two gallons of pink antifreeze with me. Sanitary wipes are a good substitute for running water for additional cleaning of hands, etc. 

Roadtrek's manual about Winter Use
Here is some of the text of the Roadtrek manual for my 2013 210P (from page G-2). This is provided as an illustration and your manual may differ:

"WINTER USE: (Moderate Subfreezing Conditions, -10C (14 F)):
The dual tank system allows you to use the fresh tank system under moderate subfreezing conditions by allowing you to isolate and drain the exterior fresh water tank.
During winter use:
  • Use gravity fill of interior tank only. [My Comment: This tank has about 10 gallon capacity and that gravity fill is on the right rear door jamb. Adding water to this tank requires a fully open rear door while pouring water via a funnel or container with attached hose into the fill point. This is not something I want to do in sub freezing conditions].
  • No outdoor shower (close the "mystery valves").
  • Waste water tanks are unprotected from freezing unless charged with antifreeze.
  • Interior temp must be maintained above 65F (18 C). 
  • Fridge must be turned ON.
  • Exterior fresh tank must be drained.
  • Exterior shower and city fill valves (Picture G-P7) must be closed and shower and city fill (See Picture G-P0) must be drained. 
  • To drain the city fill, depress the center of the check valve (figure G-P0) with a finger or blunt object to release the pressure and drain the water or antifreeze."  
  • [There is additional info in the manual and additional steps] "To prepare your motorhomes fresh water system for winter use you must do the following:"   [See 2010-2013 210P Manual Page G-2]....This is basically about winterizing the Roadtrek. 
Avoiding freezing of the gray and black tanks
Using portable fresh water containers (1 gallon or so) and then adding pink antifreeze to the gray and black may forestall freezing of other liquids added to those tanks, but there is no certainty. Furthermore, there are limits to the capacity of the grey and black tanks. Pink anti-freeze is good to about -51 F.  If we add pink antifreeze to our toilet after use, that will improve the freeze temperature of the black tank contents, but the antifreeze has been diluted and is no longer capable down to -51F.

The gray tank in my 210P has 23 US gallons capacity. The black tank has 10 US gallons capacity. When those tanks are full, we are then required to find running water and toilet facilities in fast food restaurants, restaurants, truck stops and so on, until the tanks are dumped. Some campgrounds do keep their bath and toilet facilities open in sub freezing conditions; some simply shut down for the winter.

Blog Post about Winterizing

What to do if we do get caught in a weather change to sub freezing conditions?
This happened to us once. We weren't winterized and we determined a sudden weather pattern change had occurred and sub freezing weather was coming. Predictions indicated we would experience lows below 15F for several days, unless we could travel out of the cold zone. This gave us mere hours to winterize. We dumped the fresh water tanks and water heater and then added pink (potable) anti freeze to the fresh system and the gray and black tanks, which did have some liquid in them.

But what if we had no pink anti freeze? In that case I would have dumped the fresh water tanks, opened all faucets and drained as much fresh water from the system as possible by gravity and also with the water pump (don't forget those outside shower lines and valves). I would consider remaining stationary and run the engine in an attempt to keep the underbody warm, and that includes the gray and black tanks, and any exposed piping. I would also have kept the interior at above normal temperature. At that point I would have crossed my fingers.

There are practical limits to this approach. If the weather falls into continuous sub freezing conditions for more than a day, well, there is only so much gasoline in the tank, and when moving there will be no engine heat in most of the underbody area.  In other words, I prefer to winterize under controlled conditions.

Have you ever dumped the gray and black tanks in sub freezing conditions?
For one thing the macerator is outside and might be at sub freezing temperatures. For another, that standard, thick green Roadtrek dump hose will be very stiff and you may not be able to get it to stretch.

We cut off that green hose in the box and attached a "Thetford" Sanicon slinky hose, which can extend to about 20 feet. However, it too becomes stiff in very cold weather.

All that remains of the original dump hose. Sanicon is black hose attached at the right

Thetford Sanicon hose on my Roadtrek, fully extended

Comfort Tips
Our lowest recorded outside morning temperature, while trekking and overnighting in the Roadtrek; in the morning our outside temperature monitor said we were at 3 F. This was the official temperature in Roswell NM that morning:

How we deal with cool to cold weather
  • If you have a generator, keep it serviced and exercised. We have used our Onan 2.8 kW  in sub freezing conditions. Be sure you use oil rated for sub freezing if you are winter trekking. See the Onan manual about this.  I use Seafoam gasoline additive in the Chevy gas tank before exercising the generator, which assures there is additive in the carburetor bowl. If I use the Onan on a trek, when we stop and decide we won't be using it in the near future I add Seafoam to the gas tank again and run the generator and exercise it. This draws conditioned gasoline into the carburetor. In this manner I'm not adding Seafoam to my gas tank with every fill.  There are other additives, too. Use the one that you prefer. 
  • Make sure your batteries are in good condition. More on coach batteries later in this post. For even more information, I have other blog posts on the AGM batteries in my Roadtrek, charging, etc. 
  • We fill the propane tank before trekking and we conserve propane.  The hot water heater and the furnace require propane. So does the 3-way refrigerator if we are off the grid. The refrigerator works best on 120VAC or Propane. Running the refrigerator on 12VDC only can quickly draw down the coach batteries, so we avoid that. We don't use the dual burner cooktop. We save that precious propane commodity for comfort if trekking in cold weather. If we run out of propane the furnace won't work, nor will the hot water heater. Of course, we can run the Onan generator and we can heat water in the microwave if necessary but there is no substitute for the propane furnace if we are off of the grid and don't use the generator. 
  • We travel with the expectation that the Onan generator may not start; that's never happened, but there is always a first time. If the Onan doesn't start then we only have 12VDC and Propane as energy sources when we are off the grid. The vehicle engine can be run to heat the interior. Our portable electric heater is a maximum 1500W and the Suburban propane furnace is 16,000 BTU. The furnace provides about three times the heat of the electric portable heater.  But we only have about 8 gallons of propane on board (10 gallon tank 80% fill). 
  • I carry some spare parts and tools. I think some tools are essential, and I chose to carry a few spare parts, too. I have another blog post on this. A summary: I carry a spare anode for the hot water heater, assorted small batteries, fuses, wire, spare Thetford Sanicon hose, spare macerator pump, and an assortment of latches for this Roadtrek. Several lubricants (light oil, WD-40, lithium grease, silicone). Basic tools include screwdriver with replaceable bits including square, phillips, flat. A small hacksaw,  channel lock pliers, needle nose pliers, Volt-Ohm meter, ammeter, kill-a-watt electrical device, crescent wrench, socket set, 1-1/16 socket for anode, electrical tape, teflon pipe tape, duct tape, EternaBond White Mobile Home RV Rubber Roof Repair 4" wide, glues, assorted electrical connectors, crimping tool, soldering iron and solder, etc. etc. I probably carry more tools than most would, but when we stop I then use these tools for making any modifications I may desire. (Note: strictly speaking, WD-40 isn't a lubricant, but it is great for cleaning parts prior to applying a lubricant). I do carry two gallons of pink anti-freeze; we have had to re-winterize "on the fly" once, and having that allowed it to happen; we did it in a gas mart when a sudden weather change dropped temperatures from 50F to about 10F.
  • Insulating door blanket or folding mattress. Put an insulator against the interior of the rear door. The doors have little or no insulation and a lot of metal surfaces and glass. Use Reflectix in the rear windows. Metal conducts heat from the interior of the coach to the cold outside. This cools the interior. You will feel this. Because we sleep in the rear and immediately adjacent to those doors, anything that insulates them makes sleeping more comfortable.  We have used the folding mattress for the 1st and 2nd seat for this, placing it on its side and with the "wings" folded in. The long section is 37 inches wide, and each "wing" is about 18 inches wide.  The width is anywhere between 54 inches or wider when used this way:
Roadtrek Mattress vertical for use as insulator - demonstration
  • Add an electric heater if on shore power or the generator. The heat pump will only work to about 40F, but that isn't low enough to run the furnace, in my opinion. We use a 750/1500 watt 120V electric ceramic heater when the outside nighttime temperature falls below 40F.  Here's an example:
Typical small 740/1500 watt 120V heater

  • Use an electric blanket. This can really make a difference when it gets cold. When not in use we roll it up and put it in a carry bag. 
  • Dual control electric blanket (only one control shown).
  • Stage (sequence) the propane furnace. By setting the thermostat of the furnace at the lowest comfortable temperature while running the 120 VAC ceramic heater, it is possible to assure that the interior coach temperature doesn't fall too low and propane is conserved. If on shore power, the staging means that 120VAC electrical is used to heat the coach, and only if the temperature falls below what one thinks is comfortable will the furnace come on. For example, we set the "furnace" temperature at 65F while the ceramic electric heater is set higher.  However, the Roadtrek Dometic thermostat is very flexible. It can run the furnace, or it can run the furnace plus the heat pump fan, or it can run the heat pump fan continuously. One needs to set the the thermostat to accomplish this. We prefer to run only the furnace in winter. How to do this? To do so requires than one reads the thermostat manual. (If you don't have one, google or Bing "Dometic RV Thermostat" and you will be directed to YouTube videos, etc. If you google or Bing "Dometic RV Thermostat Manual" you will be directed to pdf files, etc. which provide instruction and can be viewed or downloaded). 
Dometic Thermostat
  • Use a small multi-speed 12V fan to circulate air and minimize cold spots.  This small fan fits in the channel above the side entry door. The discharge is moveable. I also have a 12V extension to reach the dash power connector. 

12V DC Portable Fan

  • A couple of versions of soft insulated grocery bags. We carry these with us and use them for shopping and extra storage for soft goods, extra groceries, etc. If the refrigerator should encounter issues we can transfer food to these and add ice, or if we want to carry cold beverages or extra vegetables, etc. we can use these.  

Insulated bags for groceries

Maintain ventilation and reduce moisture - avoid condensation
Everything we do in a RV results in moisture release into the air. Even exhaling releases moisture and that will raise the internal humidity. Cooking with propane releases moisture because one of the byproducts of burning propane is water vapor.  Cooking and boiling liquids will release water vapor into the interior.

It is important to keep this free moisture under control. Excessive moisture condenses on cold surfaces such as windows. It also adds to discomfiture because damp clothing will conduct heat from our bodies faster than dry clothing. "Cotton kills" is the old backpacking expression.

Easiest way to eliminate excess moisture that has built up in the interior is to keep the roof vent open. However in cold weather this will also release internal heat. So we prefer to avoid doing this.  If we adjust our approach to prevent interior moisture from building up, then simply normal in and out via the side door is sufficient to vent.  However, I don't put Reflectix on that side passenger door window. I can "pop" the window if I want to admit outside fresh air.

One can run the roof fan if things get out of hand. We added a Maxx-Air vent cover so we don't worry about wind or snow or sleet getting into the rig while the fan lid is "open." That works with keeping birds and insects out, too.  The also allows us to easily open the fan vent cover even in the worst weather conditions.
Vent Cover
Cooking techniques to reduce interior moisture and reduce condensation. 
Cooking can be a significant source of interior moisture. Because burning propane releases water vapor (it is a byproduct of combustion) we don't use the propane range top. Instead we use:
  • Induction electric burner with cast iron.
  • Microwave convection oven.
Cast iron. Easy to clean, does require seasoning after repeated use and cleaning. Use a small amount of oil, spread it on the interior and heat until it is glazed.  We cover the food when cooking to reduce moisture release into the interior.
Induction electric burner with cast iron griddle
Grilled Steak on inductive cooktop

Can cook almost everything with cast iron, even outdoors if it is dry
cover removed for photo

Microwave convection oven. Great for boiling water and general cooking. Again, we do keep things covered. A silicon vegetable cooker works well.

Silicone for cooking vegetables in the microwave
Convection Chicken

Understand Your Heat Sources
In our Roadtrek we have several heat sources. We added two more:
  • Solar (sun striking the van and entering through windows),
  • Heat Pump,
  • Propane Furnace,
  • Thermostat (which controls the above),
  • 120V ceramic electrical heater (which we added),
  • Dual control electric blanket (which we added),
  • Reflectix. This doesn't add heat, but it does reduce heat loss, which is as valuable as any of the above,
  • 250 Watt electric radiating panel (which we use in our TT and 5th wheel),
  • Programmable 120V thermostat (which we use in our TT and 5th wheel to control the radiating panel).
The last two above are something to consider if you want an alternative to the 120V ceramic heater, or something to radiate energy into the sleeping area. However, the surface of these panels can get very hot. Which is why I have yet to use it in the small confines of the Roadtrek.

Sources of  Energy for heating and cooling
The sources of energy are what one has to rely upon in cool to cold weather. These include:
  • Vehicle engine heat
  • 120VAC shore power
  • 120VAC generator
  • Propane
  • Solar heat or solar power
  • 12V coach batteries (powers the furnace, etc.)
To heat the coach there has to be sufficient coach electrical energy available. For example, the propane furnace has a 12VDC blower and 12VDC ignition system. No 12VDC means no heat. These 12VDC systems will charge if on shore power, a generator or via solar. But when night falls, one must have sufficient electrical energy available. Or spend the night in sleeping bags.  I carry one sleeping bag, but we've never used it when trekking together. I have used it while "boondocking" alone.

As anyone who has spent any time winter camping can attest, merely sleeping in bags means a lot of moisture we exhale will condense and freeze on any cold surface. Back when tenting, we'd hang a towel over us to collect most of that moisture which was exhaled. The moisture was collected and froze on the towel......

In a RV moisture will collect and freeze on the coldest surfaces, and that includes the glass windows of your RV.

Solar Heat
We can benefit from solar energy. Parking with the RV facing the sun, so those solar rays enter the front of the RV can be very beneficial during daylight. Infrared energy turns to heat upon striking a solid object, be that the floor or the chairs, or you. (I'm not going to get into descriptions of black body energy situations, which are not useful for real world trekking).

Know the condition of your coach batteries
Batteries are extremely important if we are not connected to AC shore power, running the vehicle engine or an Onan generator. If fully charged, your batteries may provide you with sufficient 12VDC for the night, if you are not on 120VAC. However, repeatedly discharging AGM batteries below 50% will reduce their lifespan and capacity. For that reason I use a digital meter to determine the actual coach battery voltage. This provides me with the knowledge of when I really should begin recharging them. The lightbar in the Roadtrek is not sufficient in my opinion.

Here's some approximate battery data for AGM batteries:
  • Full charge = 13.00 V.
  • 80% charge = 12.50 V.
  • 50% charge = 12.05V (minimum for extended battery life).
  • 25% charge = 11.75V.
Roadtrek battery voltage (condition) indicator and alternatives:
Roadtrek Battery Voltage Indicator - very rough indication

Plug-in battery voltmeter, inexpensive, at Amazon and elsewhere

Location of 12V socket in  my 210P. Use a "splitter" to connect two things to this socket,
this is the location to plug in the 12V DC voltmeter

Our current coach battery monitor - measures and displays voltage and amperes.

Know the outside, interior and refrigerator temperatures
We have a couple of different approaches. The first is a typical time/date and temperature thermometer which includes a remote battery powered sensor. The remote can be put in an outside compartment to provide some idea of the outside temperature. In the photo taken at 6:38 am local time, the inside is 78.1F and the outside compartment is 15.4F. The actual outside temperature was lower.  We monitor the refrigerator temperature. This is more critical in hot weather. We simply want to avoid spoilage if something goes wrong and the temperature increases. We like to avoid unplanned stops. We carry a soft cooler bag for purchasing groceries, and we can always put critical food in it with ice if a refrigerator malfunction should occur. 

Coach and outside compartment temperature monitor - remote monitor is in outside compartment

Here's another inexpensive inside/outside digital thermometer. We use this to monitor the refrigerator, but the remote could certainly be used for outside temperature monitoring:

Temperature monitor with remote - we place the remote in the refrigerator
A real camping experience in an all electric Class B
This is what early morning in an all electric class B (not a Roadtrek) with solar panels and a small ceramic heater was like. We were on shore power. We've significantly improved on this:
Dawn at about 18F outside and cool inside
Here is the way it is in our Roadtrek, under similar conditions, after our improvements and adjustments. We were either on shore power or running the generator at the time of the photo:

Another Dawn - 33F, preparing to depart

Frozen in Texas
Frozen in Southern Indiana

Cold and damp in Georgia

Plugged in below freezing - that electric cord is very stiff at 15F. We are not using exterior water

Dawn,  6 F, the Reflectix has been stowed and we are about to move on

Having left the campground, we are headed to warmer conditions


  1. I've made a few updates, to expand the post. 10/23/2019.

I am not promoting winter camping. This post is about being comfortable in cool to cold weather and about the things we did to make our Roadtrek more comfortable in such conditions. There are other issues, including winterizing the water systems when it gets cold. The most recent Roadtrek manuals detail this very well, and are available on the Roadtrek official company website. I have a post about this.

Are we happy about trekking in below freezing conditions? We are very pleased with the ability of the 210P to keep us comfortable in cool to cold weather. We are also satisfied with the steps we have taken to improve our comfort and and we handle winter issues very well in the 210P.  It has been a learning experience and using some common sense.  We prefer to move beyond cold weather as quickly as practical when we do encounter it.......

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