Dometic/Waeco CRX 110 fridge not cooling

[dtptrailerforum55]

Looking for a little advice. My 3 year old CRX 110 runs on either AC or DC power. The unit starts up under either power source and all lights are blue. The compressor and cooling fan are both running (the coils connected to the compressor ware warm, but not hot). My problem is,, the freezer gets real cold but the fridge area doesn't get cold

at all. I took the thermistor out and tested with my multimeter and it seems to go up and down quickly when I run it in ice and take it out. Faulty ccontrol board? Ammonia/compressor fluid problem? Something else? Tks.

 

[C lectric]

No one yet?
I suggest phoning the mfgr. for some advice if not already done.

I do wonder though if the heat is having difficulty escaping the cavity. This has been discussed here many times over the last few years. If the boat side that has the fridge is getting heated , SUN, then the fridge may not be able to dump the heat.

Is there a fan blowing to the outside or at least to the saloon? If not then check the temp in the fridge cavity. at about half way up. There are transmitting temp sensors around. I got one ,although years ago now, from Radio Shack. Buy a remote reader. Mount it inside near the cavity top and see what it says. The remote will tell you the cavity temp at the top.

On my own, now older boat I had similar trouble, batteries dieing to soon, fridge running constantly with no shutdown for hours on end untill the sun disappeared. Mine was made worse by black paint on the sunny side where the fridge was located..
Anyways I modified my Norcold with the old swing motor and adapted a fan of suitable voltage to blow to the saloon inside. Made a world of difference although not perfect.
A few year later I changed fridges and got a 12DC/ 120V Ac fridge. THe mfgrs. made provision for a DC fan to br run and controlled , ON/OFF, by the fridge. THs time I exhausted the heated air directly to the exterior and it works very well.

One caution , use only one fan. Two smaller 3" ones sounded like an aircraft taking off. NOISY. The single larger 4"fan is almost unnoticeable. It turns on/off to regulate the cooling and is barely noticeable.
They and it, 4", exhaust now directly to the exterior.
The fans are typical so called computer fans drawing about 100-150 mA at 12 V.
Did this about 10 - 15 yrs ago.

But the fridge MUST be able to dump the heat to the exterior easily.
If you have no venting to the exterior then you very likely need it.

 

[dtptrailerforum55]

Thanks. I did try phoning phoning Dometic several times and they weren't much help. Appreciate your suggestions.

 

[luna]

I am not familiar with a Dometic CRX 110, but if the evaporator forms part of the freezer compartment's floor as it does in a lot of small refer units, I don't see how an internal airflow issue is causing the problem as the cold air just drops into the fridge area of the unit. If the evaporator itself is iced up, defrosting it may help.

You should have a really good look at the door's gasket as any failure of the seal between the door and the cabinet may result in the symptoms you describe.
One way to check the gasket's seal is to, from an old plastic bread bag cut a piece about 1 1/2" x 12". With the door open, place the plastic strip across the gasket and close the door. Now try to pull the clamped plastic strip out. Be gentle, if it does not come easily it is sealed.
Work your way around the door 1 1/2" at a time.

Are there any other ways that the fridge or freezer compartment can leak air?

 

[SteveK]

Since there are no direct answers, I will relate.
My at home fridge had this issue. That is when I learned how it works. The freezer has the coils that freeze. Then the fridge main gets cold air from the freezer regulated by a louver that opens and fan forced air circulates. I heard the fan running but no air was coming out. The end solution was to defrost totally. I suspect the air channel was blocked with ice. worth a try.