There is a lot of controversy in the RV community about Propane refrigerators and their safety. I won’t spend a bunch of time trying to educate you about the potential fire hazards of absorption type refrigeration units but search the web and you will find many discussions about how safe or unsafe these refrigerators really are. For us, our pets, and our belongings not having a overtemperature shut-down device is just being pennywise and pound foolish. Just to be open and honest, the number one causes of RV fires is not the refrigerator but electrical fires. The most common causes of RV fires are;
- RV Propane Refrigerator Fires
- Electrical issues – 12V shorts and batteries
- Propane gas leak
- Drivetrain issues
- Wheel bearings and brakes
- Heating appliances
- Cooking
Our 2013 Greyhawk has a Norcold N821 absorption refrigerator. This generation has some over-temperature safety features built in however I decided to install the ARP “Fridge Defend V5.1” as an added precaution. The unit consists of a small control box that interrupts the 12VDC power to the Norcold refrigerator control. When 12VDC is removed from the refrigerator controller the propane gas valve is closed and the 120VAC supply is removed from the refrigerator (our Norcold is a dual unit, meaning will operate on 120VAC aka ‘Shore Power’ or Propane Gas). So either operating on Propane or Short Power, removing 12VDC from the Norcold controller shuts the refrigerator down.
The ARP version 5.1 differs slightly from version 5.0 in that it adds cooling fans to cool the exterior of the refrigerator to improve efficiency. Most RV refrigerators are packed into tight areas with little air flow, so adding fans can significantly increase cooling efficiency.
The above photo captures my ARP controller with some of the wires terminated and ready for installation. The twisted pair wires are the thermistor sensor leads, the thermistor is actually placed on the flue tube of the refrigerator and it’s leads are then plugged into the twisted pair wires mating connector. The Red lead is power to the ARP and should be fused, in my case I used a 5 amp fuse; the type used on our coach chassis wiring. The Blue wire is the fan control and tied to the fans +12VDC lead. In my version two fans are used and I have this Blue wire pig-tailed to a “Y” connector so the fan can be modularly connected. The negative leads to the fans are tied to the Green ARP wire. The Yellow lead is the +12VDC lead to the Norcold controller. By using connectors on all wires, no factory installed wiring needed to be cut or modified. The thin black wires are the fan thermistor wires.
The above photo captures the final installation. The twisted blue/white wires connect to the lower fan. This fan draws air from outside the fridge and forces it through the external fins of the fridge. The top of the fridge has a similar access panel and ideally a fan should be installed to pull warm air from the fridge and force it outside. In my installation there is no room to mount the standard ARP cooling fan. I will have to find a smaller cooling fan and squeeze it into the small area atop the fridge at a later date.
The above photos capture the mounting of the lower fan and shows the connector used.
Velcro was perfect for mounting the ARP controller directly atop the Norcold controller.
The silver tape area is the fan sensor thermistor mounted in place. A ty-wrap was used to secure the wires in place.
The most difficult step in adding the ARP controller to the fridge was accessing the flue and placing the thermistor onto the flue tube. These are the wires with connectors at the end of the thermistor. I installed the thermistor a few weeks before installing the controller since I felt it was going to be the more difficult step.
You can learn more about ARP and how it can help protect your refrigerator from an over temperature condition but going to ARP’s website; https://www.arprv.com/products.php
Coachella 