Waeco compressor fridge - freezer issues!

[RichardA]

Dear all,

I posted a question re CR-65 freezer defrosting some time ago and got a couple of responses. The issue is, I believe, quite 'entrenched' and I thought I'd solicit views and experiences.

There appears to be nothing untoward with the fitting of my fridge that could cause the problem, A Waeco engineer believes there's nothing wrong with the fridge and yet a brand new fridge (supplied my very understanding van 'converter') has much the same problem. I've turned into a bit of a fridge geek and bought and fridge/freezer thermometer. This has 2 remote probes for measuring temp of both fridge and freezer without having to open the door. It has also has min/max readings so I can measure what's been going on at any point in time. After several days of constant measuring it seems that while the thermostat controls the fridge temperature quite reasonably it certainly doesn't handle the freezer at all well.

On a setting of 4, the fridge cycles between 5.7° and 8.6° while the freezer cycles between +0.3° and -22.8°. The freezer stays below zero during the day but just creeps above zero overnight when the ambient temperature drops.

Turn the setting up to 5 and the fridge cycles between 3.5° and 7.0° while the freezer cycles between 0.0° and -24.5°.

I suspect that this is the way ALL compressor fridges are working but few people notice. If so, it's exceptionally unhygienic let alone annoying. I've communicated with a very friendly Waeco engineer in Australia where it seems this problem is acknowledged on their 'tropical' rated fridges and a revision kit has been developed - not available in the UK. I'm having great trouble getting communication going with Dometic in the UK!

Has anyone else noticed this problem? Or is there anyone out there geeky enough to try and take a few measurements?

Regards.

Richard

 

[AndyC]

I 'think' that the Waeco CR range features automatic defrosting. This would account for the cycling in temperature. We have one of their MDC range and I'm pretty sure that these don't have a defrost cycle.

The automatic defrost shouldn't be a problem if you have a quantity of frozen food in the freezer compartment, the temperature of the food shouldn't rise high enough to start it defrosting, however I guess it could be an issue of there only a very small amount in there.

AndyC

 

[hextal]

I've not fitted my CR-80 yet, but on reading the instructions they are designed for ambient temperatures of 18-42 degrees C. Though other makes of compressor fridge appear similar.

From what I can gather (and take with a pinch of salt as i'm still working it out too), the fridge is the key element and controls the thermostat/compressor with the freezer element being more a bolt-on element (again seems similar in most makes). As the ambient room temperature drops closer to the desired fridge temperature the compressor will run less and less, until it doesn't need to run at all when the ambient and internal temperatures match. Now, evidently, the freezer also needs the compressor running, but has no independent control, so it will also only cool when the compressor is running for the fridge. So, the cooler the ambient temperature, the less demand on the compressor from the fridge, the more the freezer will defrost between cycles.

I'm guessing that this may be what is happening.

I know its an old trick, but have you tried freezing something fairly dense (in the domestic freezer) and putting it in the camper-van freezer to act as a means of 'damping' the temperature fluctuations between compressor runs.


[as I say, the above is what i've gleaned thus far, so may not be 100% bang on]

 

[vwalan]

a friend had one in their camper and they had trouble as it was a tropical fridge and not a normal one did just what op as just said .
although they were in morocco it was winter it kept defrosting then freezing . they had it change for a non tropical version .worked a treat .