Hi everybody.

Thanks for letting me join. A family member dropped off a camping fridge/freezer for me to have a look at. It is not a commercial device, apparently a local firm made a run of them some years ago for a specific purpose. It is very nicely made, fully stainless steel with a Danfoss BD-3F compressor and controller, dual thermostats, one for fridge one for freezer, is capilliary and has a replaceable filter/dryer fitted. The condenser is a coil inside a vertical tube with a fan at the top.

Now I am an electronics tech, so I know enough to be dangerous about refrigeration and in Australia I can't legally tinker with the refrigeration side of things, so I just need to determine whether it needs to go to a fridge mechanic or not. It's 12 volt, so no dangerous voltages to worry about.

If there was a sticker indicating the refrigerant and charge, it is long gone. Google suggests that the compressor can use R134a or R22.

So my task was to clean up the engine bay and run some tests as he said it was constantly drawing current.

It was full of good ol Aussie red dust and the fan wiring was bad, so I fixed that and ran her up. One thermostat is for fridge mode and the other freezer. In fridge mode it seems to work fine after a clean and adjusting the thermostat.

In freezer mode it just keep running the compressor and settles around -11 deg C. but doesn't seem to go any further. The thermostat hysterisis (cutin-cutout range) seems to be around 10-11 degrees, so I can't get it to stay below zero and cutoff properly.

So my question I guess is should it go lower than -11 degrees Celsius? Ambient is around 21 C currently. Or is the thermostat dodgy and its control range should be tighter?

Thanks,
Glenn.