# Dometic Refer Dead- Found The Problem And Solution



## ajk170 (Oct 18, 2015)

In case this has already been covered and resolved, I apologize for a duplicate post- if it hasn't I hope this helps somebody. This certainly applies to DM2852RBX refers and there are several others as well.

We pulled into the house from our 2017 Memorial Day holiday at Allatoona Lake, Ga and after setting the TT back in its place and beginning to unload I discovered the refrigerator was dead. No 120 or 12volt. We go through the normal trouble shooting of fuses, gas valve open etc. I go to back vent shroud (it's on the side, not on top- it's a 2015 Outback 316RL) only to find it missing! No damage to the coach, bezel, or compressor/burner. And no, There was no chance somebody didn't yank it off enroute from the lake to home. Very, very strange. The DW and I both agree that when breaking down at the lake we heard a "pop" when messing with the water and sewer shortly after turning off the power via the circuit breaker at the post (rather than simply unplugging(gun-shy from a previous issue that happened as a result of simply unplugging). We couldn't find the source of the "pop" and thought nothing of it.

So, there I am pulling the box off the circuit board on the lower control panel at home (this is right behind where the shroud/cover should be and where the drain tube comes out, but since mine is now missing, I'm starring at the little black cover that's over the lower control board/circuit board). the DW is on he computer looking Dometic for repair guides and threads in forums that talk about this issue.

So find a service guide from Dometic and I see our coach has the thermofuse with the little button on the stack. The little center reset button wasn't tripped on the fuse and continuity on the multi-meter indicated the thermo fuse had continuity. So after lots of trouble shooting, I even take a known good 12volt battery and directly wire to the terminal block to rule out breaks/shorts in the system elsewhere. Finally, I conclude its the lower control board since the service manual trouble shooting tips indicates that is the problem (ie, no power to the J6&J7 and no power to the upper control board at the P1). Plus, there is NO 12volt coming into the control board despite power at the terminal block. The 120A/C power comes directly to the control board via the J5 and J6 wires but if its not going out through the J7 & J8, the manual also says replace lower (at $100 ea). So we got the board today and replaced the orginal-(although the replacement was NOT the same as the original) and it's still dead. I call around to try and get it into a service shop and nobody can touch it for weeks. I figure I might as well replace what I can since nobody can help me right now so all that's left that's easy and cheap is the thermofuse. I see random places selling them at wildly different prices but nobody near me has any onhand except one place 80 miles away. I decide to drive there and on my way I stop at dealer where I got the circuit board to see if they have a thermofuse. After 10 minutes of the parts person searching for a thermofuse, limit switch or thermoswitch, they can't find it within their system under any of these names, despite so many other online people selling them. I finally show the parts person what I'm looking for from a competitors website and she says "...that comes in a recall kit... " and gives me a whole kit for free since it was no charge to them. She mentions to me that the kit isn't complete since the techs raid the kits for that little fuse. (that tells me this is far more common than it seems) I go home and realize mine is already outfitted with the recall kit. But I figure I have nothing left to loose, I pull the wires and old thermofuse and BAM! I'm up and running.

What I learned - all the 12volt power goes through the thermo fuse BEFORE it ever hits the circuit board. A better doagnostic on my part would have led me to discover this fact but I didn't take everything apart fully on my initial assessments. So the only piece I still need to do to the coach to ensure it's really fixed is to unplug and force it to kick into propane. I think that's where the real issue is- the "pop" we heard may have been a result of the fringe try to kick over to propane after we turned off the shore power. We normally leave the fridge on all the time. Now I'm a little apprehensive about it!

Im going to enjoy my win for the moment.

So if your Dometic 2852 (there are others that this applies to- I don't remember all the variants) is dead with NO POWER AT ALL to the unit and you have the Dometic recall kit already installed- it's probably the thermo fuse or the inline resistor that comes in the Dometic recall kit. Not sure how you get the kit since I had a hard time trying to talk to anybody at Dometic as an end-user. The customer service number never got me to a real person- maybe I was using a bad number. I'm not sure other service centers would just give a recall kit to the end-user, I got lucky (probably because I spent $100 with them and it didn't fix the problem). Nonetheless, You need a SECONDARY BURNER KIT(nobody would ever guess that as a name to the parts) which is the name of the recall kit from Dometic. That kit has the wires and the thermo fuse. Remember all the power runs through that resistor and thermo fuse before it hits the circuit card (via the J4). There is also a second thermo fuse at the top of the stack and that has a separate power line from the terminal block with a 3 amp fuse as well. Not sure what that does but didn't appear to have any bearing on my specific problem- nor did the kit have those parts. I don't really know what the thermofuse does but it appears to deal with the ignition of the propane so bypassing it may not be a good option.

Hope this helps!


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## Oregon_Camper (Sep 13, 2004)

Good info...thanks for taking the time to let us know your resolution process.


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## daves_25rss (May 26, 2011)

hmm, if the thermo fuse is the problem is there any problem with just bypassing it to see if the fridge works?

My 2652 keeps shutting off and a reset of the thermofuse fires it up for awhile.

(I also replied in another thread with the same problem )


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## ajk170 (Oct 18, 2015)

Bypassing probably would have worked in my situation but the reset was popped and it appeared to have continuity so I initially dismissed it as a problem. The part that I should have looked at closer was how electricity got to the circuit board. Once I went to replace the wires from the recall kit and the thermo fuse, I discovered that the 12volt power went through the thermofuse. The wire schematics I was looking at didn't show that either- it shows the J4 wire coming directly from the terminal black (on the 2852 version). I would want to know what's spiking that causes the fuse to trip.

And to close the loop- I unplugged to check that the 12volt/propane system would turn on and not trip the fuse and it works with no apparent issues. Even with the $100 on the circuit board, I feel good since I figure any service shop would have charged me at least twice as much! It's better when we can do these things ourselves!

What I'm most surprised by is the lack of documentation out there on the web about this- I feel like we looked through several forums with nothing talking about replacing the thermo fuse or 12volt power wire with the inline resistor. I did see a lot of people talk about pushing the button on the thermo fuse as well as replacing the 3amp and 5amp glass fuses on the circuit board. I think I saw one reference about the recall kit but it was about having it installed. I also saw a lot of things about replacing the thermofuse if the fridge isn't cooling- but nothing about the thermofuse or power wire with the resistor being the problem if the fridge is DEAD.

Again- hope this helps other people out there!


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## daves_25rss (May 26, 2011)

thanks ajk170,

I will try bypassing the thermo fuse tonight and if it works order a new one and if not I guess I will have to start looking for a new/used unit.


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## Leedek (Nov 28, 2010)

I hope this doesn't cloud the waters here. I found this URL thread that seems to shed some light on Dometic refers and thermo fuses. It sounded like a similar problem to what you are/were experiencing. Now i have to go check and make sure my refer is working both ways.

http://www.sunlineclub.com/forums/f71/blown-fuses-9622.html

Good luck.

Leigh


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## ajk170 (Oct 18, 2015)

Lee deck- any luck on the bypass?


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## Leedek (Nov 28, 2010)

ajk170 said:


> Lee deck- any luck on the bypass?


Actually I spent my afternoon getting the trailer roof cleaned and inspected. I'm confident the refer is working both ways.


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## ajk170 (Oct 18, 2015)

Leedek- that's good news! It's a good feeling when you can get it working again!


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## daves_25rss (May 26, 2011)

I bypassed the thermofuse in my 2652 and while it doesn't cut out anymore it also still doesn't cool.

Everything seems to work like it is supposed to on both gas and 110V.

Any ideas on my next steps other than new cooling unit or fridge?

If I understand it correctly the thermofuse is just shuts down if there is too much heat in the heater area and isn't actually connected to the cooling unit.

Or is that wrong?

If that is the case I am not sure how it actually knows if there is a problem in the cooling unit. 

If there is a blockage in the cooling unit is there anything that can be done to clear it?

I also have a possible line on a Norcold 662, it looks like it is almost exactly the same size and should just switch in no problem.

Is that right or do I have to change any venting etc.

Thanks


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## ajk170 (Oct 18, 2015)

Dave_25rss- I saw other posts about the fridge not cooling when mine went out but didn't pay close attention since it wasn't my specific issue. I would think bypassing wouldn't make a difference and shouldn't affect the cooling aspect but it may since I don't really know what the thermoduse does.

My unit actually had two thermo fuses one that was up by the coils and he other at the base where all the power went through- you might look to see if you can pull you top fuse and try it in the bottoms place or go to your closest RV Dealer and see if you can get a fuse from the recall kit. I think if you can get a cheap fuse to better isolate the problem it's better than dropping a lot of money and time on a new unit. I saw thermofuses for sale on line from other RV places.


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## mhrich1 (Sep 14, 2016)

I have a 2015 Outback 250 TRS and Dometic DM2652 LBX fridge is shot. Dealer said cooling unit leaked and not covered under warranty because it is 9 months out of warranty. . I have my own cooling unit coming and will install myself. I have heard the new Dometic 2652 are not well built, anyone else having problems with like new fridges? I have had many units that lasted 10-15 years.


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## petruncd (Jun 3, 2021)

ajk170 said:


> In case this has already been covered and resolved, I apologize for a duplicate post- if it hasn't I hope this helps somebody. This certainly applies to DM2852RBX refers and there are several others as well.
> 
> We pulled into the house from our 2017 Memorial Day holiday at Allatoona Lake, Ga and after setting the TT back in its place and beginning to unload I discovered the refrigerator was dead. No 120 or 12volt. We go through the normal trouble shooting of fuses, gas valve open etc. I go to back vent shroud (it's on the side, not on top- it's a 2015 Outback 316RL) only to find it missing! No damage to the coach, bezel, or compressor/burner. And no, There was no chance somebody didn't yank it off enroute from the lake to home. Very, very strange. The DW and I both agree that when breaking down at the lake we heard a "pop" when messing with the water and sewer shortly after turning off the power via the circuit breaker at the post (rather than simply unplugging(gun-shy from a previous issue that happened as a result of simply unplugging). We couldn't find the source of the "pop" and thought nothing of it.
> 
> ...


Hi had the same problem, found out from a youtube video, I ordered the thermo coupling from Amazon. Thanks for the great info you shares.


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## sportymike (5 mo ago)

thermofuse is:
https://www.amazon.com/gp/product/B...icro Thermal Fuse 10A 250V,-Brand: CompStudio

resettable disc thermal switch on metal tube is:








Amazon.com: DOMETIC 3850870019 Thermofuse Fpr DM2652 with - Product #958530285 : Automotive


Amazon.com: DOMETIC 3850870019 Thermofuse Fpr DM2652 with - Product #958530285 : Automotive



www.amazon.com


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## sportymike (5 mo ago)

the one time use thermal fuse will burn up and cut dc power to unit if the gas burner flames up for some reason...it actually melts this fuse. if its burnt out you may have a safety issue such as clogged flue or high gas pressure from a bad lp regulator possibly. might have just been a 1 time issue of built up gas then a late ignition in wind or something. if your outside door has blown off after a loud pop then you n
know it was a small gas explosion and you should see where you are leaking propane.

if its the resettable thermal fuse switch that looks like a little disk with small black reset button in center, those can go bad and pop too soon but most likely is that it is working fine and your boiler area is overheating on electric 110 setting from the burner area or cooling fins being blocked. if your cooling unit is bad and has leaked, i think it would be possible for that to overheat also from no liquid circulating in it to cool


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