Refrigerator not cooling

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shawn 8586

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20 degrees in frezzer 60 in refrigerator.could  a bad thermistor cause this?it's a dometic
 
Forst things first.  Look at placement of the temp sensor on the far right fin.  There are dozens of posts on how to adjust it.  Second, open the outside cover and look smell.  If you see a yellowish stain on the coils,  or smell ammonia, your cooling unit is shot.  If everything looks OK, using compressed air, blow out the chimney.  Verify the burner flame is good.
 
I've done all the things you suggested,everything seems ok, I don't get why the frezzer is fine but the fridge is warm.
 
20 degrees in the freezer is definitely NOT fine.
Are you on electric or gas?
Do you have 120VAC, 12VDC at the board?
 
shawn 8586 said:
I've done all the things you suggested,everything seems ok, I don't get why the frezzer is fine but the fridge is warm.

Sounds like you have made sure you have good air flow across the cooling unit coils and have a method to measure the temperature in the freezer and fridge compartment.  20 deg F in freezer is too warm, so it follows that the refrigerator compartment would be warm too.

One of the basic tests you can do to determine if the cooling unit is working is to bypass the control system (control board) and run the electrical (AC) heating element directly.  The refrigerator control board simply cycles the heating source (AC heating element) or LP gas burner on and off to achieve temperature control inside the refrigerator. Below is a link to a video describing how to do this.

https://www.youtube.com/watch?v=k2bBSGuwU_o

If after doing this test, the result is GOOD, then you can rule out the cooling unit and determine if the problem is in the control system (control board, thermistor, etc.)
 
shawn 8586 said:
I've done all the things you suggested,everything seems ok, I don't get why the frezzer is fine but the fridge is warm.
-You are 20degrees out of spec on both. Not good. But..
-Elect, gas, or both?
-Measuring with or without contents?
 
I've got it switch to gas at the moment, I had a transfer switch go bad and I'm wondering if it may have burnt the board up on the refrigerator. I have it on plugged right now waiting on a transfer switch to come.
 
My apologies if this sounds pretty dumb, but is the temperature set low enough on the thermostat?


I only ask because you did not specifically mention that you had checked that, and it appears that the fridge is working at least to some extent.
 
The freezer gets priority from the cooling system, so a poorly functioning cooling unit can still keep the freezer frozen while the fridge part gets warmer and warmer. The thermister doesn't affect the balance between freezer and fridge, but moving it can make both colder or warmer.  I seriously doubt if the thermister is related to your problem.

As others have said, 20 in the freezer isn't great either, about 10-20 degrees too high, so I suspect you may have a cooling unit failure.  First, though, we need the model of the Dometic, and the age would help too. Also, is this a recent problem (was working OK last week/month) or an ongoing thing you are just getting started on?

Have you tried both LP gas mode and electric? If both produce the same results, the number of possible causes is much smaller than if one or the other works better.
 
its a 2004 dometic,model RM 2852,it does the same thing on LP or 120v. ive had it about a year and its done fine just started not cooling good a week ago.could a bad control board cause this?
 
You need a new cooling unit.  Amish cooling units get good reviews as better built and less money than dometic part.
 
shawn 8586 said:
its a 2004 dometic,model RM 2852,it does the same thing on LP or 120v. ive had it about a year and its done fine just started not cooling good a week ago.could a bad control board cause this?

Another forum member posted this link recently, Shawn.  It deals with your question and is one video that is worth your time to view.

https://www.youtube.com/watch?v=k2bBSGuwU_o

Good luck with the fix and safe travels.  ed s
 
Okay here's what's going on, I bypass the board and straight wired it to the heater and let it sit for 2 days and my freezer got to 5 degrees and my refrigerator got to 32 degrees, so do I have a bad thermistor or a bad board?
 
It looks like you have a control board failure since the cooling works when you bypass it. One last thing return the system to normal and remove the thermistor from the fins and let the refrigerator run for a day and see what temps you have. I have read else where on this forum that if you do this and the temps are good the termistor is bad or you need to adjust position on the fins.
 
If you have an ohmmeter you can test the thermistor.  Just follow the instructions in the troubleshooting guide.
 
I posted somewhere where I had a transfer switch go bad and so I ordered a new one and put it on and now the refrigerator works perfect 38 degrees in the fridge 10 degrees in the freezer and all I've done was change the Transformer switch. I would never in a million years think that a Transformer switch would have anything to do with the refrigerator Cooling even on gas it's working fine.
 
shawn 8586 said:
I would never in a million years think that a Transformer switch would have anything to do with the refrigerator Cooling even on gas it's working fine.
Well, can't imagine there's any connection, but if the beer's cold don't fight it!
 
The thermister is the same whether gas or electric, so if the gas mode works the thermister is fine. Since you say gas & electric are both poor, the thermister is a possibility, but it must be working somewhat or there would be no cooling at all.  Have you moved the thermister on the fins? Further out towards the edge makes the controller run the cooling unit longer (cooler).

Your jumper proves the cooling unit is OK, but the same controller runs gas & electric mode, so chances are the board is OK. I'm leaning toward thermister or the wring between board and thermister. Find a free service manual for your Dometic at the site belwo and start thermister checks.
bryantrv.com/docs.html

 

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