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Tue Sep 01, 2020 8:35 pm

Hi, my Dometic stopped working on 110V as the heater element has failed. Does anyone know where to source a new element? Several suppliers seem to have the 12V but I can't find the 110V (listed as 120V in the manual).

Alternatively, does anyone know the wattage on the 110V so I can track a similar one down? Some RV equipment suppliers sell fridge heating elements which look similar in several different wattages. Is there one out there which is a close match?

Thanks in advance!

Wed Sep 02, 2020 7:05 am

If you can't find a wattage directly - can you find a working element and measure the amperage? Amps times volts = watts.

Does that hep?

Wed Sep 02, 2020 7:54 am

I would try to source one in the classifieds. Lots of people get rid of the Dometics after moving to more modern fridges.

Wed Sep 02, 2020 10:49 am

Search the internet for the "RM182B Dometic service manual" .pdf.
It's easy to find for free download.
Likely some of the Vanagon websites have it too.

Probably in the Samba stickies too.

Wed Sep 02, 2020 11:38 am

Searching "dometic fridge heating element", most of the heating elements I see are L or curved L shaped. e.g. 160 Watts, 110 VAC for the RM66E, "among others":

http://getrvparts.com/dometic-0173719014-rv-refrigerator-heat-element/

It's likely a higher Watt element than is needed but if something like that fit, would leaving part of the element exposed be a a fire risk and/or risk prematurely burning out the element? I'm nearly certain that the one piece AC/DC element(s) or separate AC DC elements on the 182 are not tight a fit. There is a screw that holds them in place.

Wed Sep 02, 2020 12:30 pm

Hi all, thanks for the replies.

Unfortunately the RM182 manuals online do not give any clue as to the specifics of the heater elements but one of the papers I read did say it was very important to match the correct heat output to the fridge. Not sure exactly what they mean but I think the element needs to be very close to the same output.

Interestingly, I decided to pull the fridge and have a look and see if there were some markings or parts numbers on the element which would help. The elements hooked up to both the DC and the AC appear to be identical! Does this make sense? It doesn't from by rudimentary understanding of electricity but it does explain why our venders only have one element available. Most don't identify it as 12V or 110V but one calls it 12V.

So, maybe the issue isn't no one sells the 110V element, it's that the one element works for both. Seems like a strange answer.

Wed Sep 02, 2020 12:32 pm

While the heat output might be the same, the circuits the AC and DC elements works off are separate. i.e. there is no means built onto the fridge that would step down and convert AC shore power to something that would work with a 12 volt DC element.

edit: ..... but, something like a heating element may not "care" if power fed to it is AC or DC so I get where you're headed with this.

Neil.

Wed Sep 02, 2020 3:54 pm

I think this is what you are looking for. Resistance check 140 Ohms. Definitely came off the 120V circuit of the fridge. Slowly getting the fridge down to carcass status. PM me if interested, it's free.

Out of curiosity I checked the resistance of the 12V element it's: 2.1 ohms.

Watts 120V approx: 100W
Watts 12V approx. 70W

Wed Sep 02, 2020 5:05 pm

Ok, so not the same element. Thanks Farf, exactly the info needed. I'll be trying to track down a used one I guess....

Wed Sep 02, 2020 8:13 pm

The tag inside the Dometic fridge states 7 amps on 12 volts. 7x12= 84 watts. It also says .7 amps for 120volts. Which is also 84 watts. But I don’t remember from the last time I changed one of the heaters if they were the same. I know I have a used one somewhere. If I can find it tomorrow I’ll report back if it’s a 12 volt one and if there is a part number on it.

Thu Sep 03, 2020 8:48 am

I found my 12 volt heater element. My fridge quit working on 12 volt years ago and I had ordered a new element after testing for continuity through the heater circuit with the fridge in place. When I pulled the fridge to replace the element it turned out to be just a bad connection in the junction box where the element leads connect. I have a tin top to camper conversion on the go so I'm not looking to sell this element. Just wanted to share the info to help others.

Thu Sep 03, 2020 12:33 pm

jordauto wrote: The tag inside the Dometic fridge states 7 amps on 12 volts. 7x12= 84 watts. It also says .7 amps for 120volts. Which is also 84 watts. But I don’t remember from the last time I changed one of the heaters if they were the same. I know I have a used one somewhere. If I can find it tomorrow I’ll report back if it’s a 12 volt one and if there is a part number on it.
Just because they are the same wattage does NOT mean they are the same part! You'll have a fire somewhere if you connect the 12V one to 120V... either in the van or the main fusebox!

Thu Sep 03, 2020 1:32 pm

Oh no, I wasn’t suggesting they are the same. The 12 volt one clearly says 12 volt on it. I just wanted to add that information to this thread in case someone is searching for heating element information in the future. Sorry if it wasn’t clear.

Thu Sep 03, 2020 7:01 pm

I didn't write down my source for this, but I found this in my notes.

Dometic heating elements:
12 V DC = 85 watts, 1.7 ohms, 7.1 amps, PN 2929375042
120 V AC = 85 watts, 169 ohms, .71 amps, PN 2929374045

For 110 V AC = 85 watts, 142.3 ohms, .71 amps

Dimensions
RM182B H 23 1/2", W 17", D 17 1/4"

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Dometic Refrigerator Diagnostic Service Manual