Adding Refrigerator Exterior Fans

Photo During Construction!

The sun is a beneficial thing in RVs in the winter. Most RVs have a lot of glass, and that surface area loses heat in the winter. So sunshine is a good thing. However, in summer the sun can contribute to discomfort and can interfere with operation of the refrigerator.

When we trek, we sometimes park in full sun and occasionally in partial shade. More often than not we don't get to choose the orientation to the vehicle to the sun or the amount of sun we receive.

On a trek a while back we were in a location where we and a lot of other people were in full or partial sun. The outside temperature in the shade peaked at 103F (39C). To make things worse, the vehicle was oriented so the afternoon sun was full on the side of the vehicle that houses the refrigerator.

Our Class B has a single door Dometic refrigerator. This is the absorptive type, which does not have a compressor. It works well, but is slow to cool from ambient temperatures. It has rear radiators. The radiators are behind the refrigerator and two grills on the side of the RV provide cooling of the radiators via convection. "Cool" air enters the bottom vent, passes through the radiators and the compartment cooling them. It then exits through the upper vents.

On our trek which reached peak temperature of 103F the refrigerator struggled. We weren't alone and a lot of rigs both big and small had similar issues.

We decided to do something about this. Short term, some people put a bucket of ice in their refrigerator. That is not always practical. First, one has to find a source of ice. Second, that bucket takes up interior space, which is precious in a 5 cu. foot refrigerator. Third, the water has to be disposed of. If a covered container is used, as the ice melts it won't slosh around while moving, but otherwise it can get messy.

The other choices we considered included one active and one passive supplemental cooling technique. The passive one was to add a moveable sun shade. However, we usually orient that in such a way as to reduce sun on the front of the vehicle, where most of the glass is. The other was to add electric fans to improve the airflow behind the refrigerator.

Dometic has instruction on how to do this for both single and dual door refrigerators. Here's a link to the single door instruction. Dometic also has instructions on the web for their dual door refrigerators:
Dometic Power Ventilator Instructions

Installing these will vary from model to model and that includes the details of the RV. I chose a location directly behind the upper vent openings. I also installed an simple aluminum strut to bolt the fans to. I used two low power fans and a thermostat mounted on the hot side of the coil. Seems to work well.