3way fridge fix
goldstream wing 3 

Our Goldstream Wing 3 camper came with a Dometic 3 way 90litre fridge/freezer. While this may be fine in cooler climates it struggled to maintain the minimum 5 degrees Celsius for safe food storage in the Queensland heat. I was going to replace it with a compressor fridge but decided maybe it can be improved to make it work correctly.

Looking at the installation instructions that came with the fridge it seems to be installed to spec with the exception of the top vent not being above the top of the fridge. Being a wind up camper that just can’t be done (its level with the top of the fridge).Looking over the many posts on this on the internet I decided to try fans to assist the cooling. Firstly I installed a 120mm fan to the exhaust (top) vent using cable ties to hold it in place. I included a plug in the supply line so I can remove the vent entirely if need be. This fan helped but was not what I had hoped for.

Next I installed a 90mm (biggest I can fit in the space) at the bottom of the condenser coils to assist with cooling. This fan made a huge difference to the cooling efficiency. Suddenly the fridge was cooling much better.

After reading many post on the internet I read that many people have had success with putting a fan inside the fridge to help with air circulation. I originally had a tiny 40mm fan in the fridge but it was too small to do anything, so I replaced it with a 80mm version. This fan sucks cold air from the bottom of the fridge and circulates it around the fridge. The small wires go through the water flow pipe opening to the back of the fridge and connect to the other two fans. This fan seems to help with reducing the water in the bottom of the fridge and also stops the cooling fins from icing up and maintains an even fridge temperature. This also helps with things being frozen overnight.

All fans are wired via a 90 degrees Celsius thermostat cable tied to the evaporator tube about 75mm from the top of the heat unit. The idea was the fans would go off when the fridge cycled off. It may never do that...I have also put in a switch to turn the fans off if need be. All 3 fans are 'silent', and are dust and waterproof and draw a total of 0.35 amps. That’s around 8.5 amps per day, but it’s a small price to pay and easily replaced with the solar panel. All three fans have a guaranteed life of 100,000 hours at 40 Celsius. All you hear is a very slight hum which is hardly noticeable.

I also installed a Fridge Switch which disconnects the 12volt supply when travelling after three minutes of ‘non movement’. Helps draining to main battery rather than relying on the battery isolator.

Original fridge ‘Auto cable’ wiring in front of Fridge Switch. Replaced with 6sqmm cable.

The fridge is running on 240 volt at the moment and is maintaining between 2 and 4 degrees Celsius. Fridge thermostat is set to half. The freezer is holding -15 Celsius. Ambient temperature is currently 30 Celsius. I also have two 500ml bottles of water I froze and placed in the fridge. Helps get temperature down initially and although thawed helps it recover quickly when opened. It should do better on gas.

Total cost around $200 for the three fans, thermostat, Fridge Switch and associated wiring.
Fans Supplier: http://www.jaycar.com.au
Fridge Switch: http://www.rvelectronics.com.au
 

Thanks to Kevin Beckwith for this article

 

january 2012