The little fridge is not acting like 3 way??

Kasey Redrum

Member
Oct 17, 2019
46
Just came back from some nice camping at Agua Caliente, full hook ups. Our little Rockwood 2005 pop up (1640), has the original Dometic 3 way fridge. Have not had issues since I bought the pop up a few years ago. But we could not get it to work using the 120v switch. There was electricity at that little outlet in the back area, but never cooled. I then tried to switch it to Propane, and I could not get it to stay lit?? I could get it lit if I pressed the button in, but as soon as I let the button up, it stopped.

So then for fun, I tried the 12v option (never did that before) and sure enough it started to cool. ?? Any ideas on what is going on here?
 

Anthony Hitchings

Super Active Member
Silver Supporting Member
Mar 2, 2019
3,489
Oakland, California
the heating elements (separate for 12V and 120V) do sometimes burn out. You can check your 120 heating element using a simple continuity tester (battery, lightbulb, wire) or get fancier if you wish and use a DVM
 

Sjm9911

Super Active Member
May 31, 2018
11,443
Nj
I would also try plugging it in directly to a cord and outlet I I kow that works, or plug something else into the camper. Sometime half a outlet goes out.
 

Sneezer

Super Active Member
Aug 8, 2015
2,958
DFW, TX
Make sure you have the switches in the right position. There are some fridges out there that have 2 or 3 switches used to select between power sources. Many people don’t get them pressed correctly, resulting in issues.

Mine just uses a rotary dial, which is easier. Propane flues get clogged with bug nests and spider webs, which causes the main flame to snuff out. 120V elements can go bad too.
 

jeepster04

Active Member
Nov 23, 2010
271
Another thing, you must hold down on the knob for a bit once the flame lights. Gotta give it time to heat the thermocouple up before you release it. Normally 10 seconds or so will do.
 

Everett Bartlett

Active Member
Aug 2, 2020
145
Southern Nevada
Something else to check is for there being dirt in the switches. I had problems with my reefer, and it turned out to be dirt in the switch, used spray contact cleaner to clean them out. Got dirt out to about start a garden. Switches just could not make contact. If you have been going to Glamas, check for dirt.
 

Raycfe

Waterford Ct.
Oct 3, 2007
18,044
Waterford, Ct
The 120 volt element should be the easiest to troubleshoot >power to the switch >power to the element > is the element burnt out.
The propane will shut off if the thermistor does send a signal to the gas valve to stay open. It is a little bulb with a small copper line that the pilot light heats up to send the signal. (some times it may take a minute or two to heat up.
 

Grandpa Don

Super Active Member
Sep 5, 2018
1,577
Southern California
Troubleshoot one thing at a time. You most likely have two different problems. Take the propane first. Since you can get the burner to light, that means there is propane reaching the burner. As stated above, hold the knob down with the flame lit for about 30 seconds then release the knob. If the flame then goes out again, then you need a new Thermocouple. Or it could be dirty or out of place in relation to the flame.
 

Kdague

Member
Sep 15, 2020
42
Check and make sure u don’t have a tripped GFCI at one of your outlets on 120.
And the flame sensor or probe or thermocouple may need replaced or u just need to hold it down longer. I would try holding the gas valve on for like 2 minutes or even more before u rule the sensor bad
 

Brandon Harris

New Member
Oct 15, 2021
3
Funny this should come up. Just had the same issue with mine and I recorded most of the process i used to fix it. Just have to edit the video now and get it uploaded. Stay tuned
 

goose10202

New Member
Jan 9, 2017
4
I've encountered this on more than one camper and the fix for the AC side was always replacing the power switch. Seems odd but they do go bad. They don't cost much and are easy to swap out.
 

Kasey Redrum

Member
Oct 17, 2019
46
IMG_9515.JPG Good ideas. So Propane troubleshoot today. I noted that if I light the pilot, I get a big orange flame from the rear of the jet? Way too big, then when I release the button it all goes out and no pilot. So I went ahead and removed the jet assembly, noted that there was lots of carbon buildup on the tube of the thermistor. Odd.... ok so disconnect from the gas line, look down inside the burner and thick dark sooty web completely blocking. Meaning when I was seeing big orange flame, it was gas pouring out of the air exchange ports, and creating a 3 inch high flame. yikes. Ok so cleaned out the jet, blew air through it and sprayed some rust deoxidizer in it and blew that out with a compressor. Rehooked it all back up and boom, now it lights and runs on propane. Hey am I the only one who cant see that damn blue flame when it is lit. Seriously I would have to lay flat on my stomach in order to peer into that hole in order to see any flame??? Thanks for all the tips. Now onto why the AC isnt working. p.s. this image is after I reassembled everything.
 

Jwwiff

Member
Jul 16, 2015
93
View attachment 79747 Good ideas. So Propane troubleshoot today. I noted that if I light the pilot, I get a big orange flame from the rear of the jet? Way too big, then when I release the button it all goes out and no pilot. So I went ahead and removed the jet assembly, noted that there was lots of carbon buildup on the tube of the thermistor. Odd.... ok so disconnect from the gas line, look down inside the burner and thick dark sooty web completely blocking. Meaning when I was seeing big orange flame, it was gas pouring out of the air exchange ports, and creating a 3 inch high flame. yikes. Ok so cleaned out the jet, blew air through it and sprayed some rust deoxidizer in it and blew that out with a compressor. Rehooked it all back up and boom, now it lights and runs on propane. Hey am I the only one who cant see that damn blue flame when it is lit. Seriously I would have to lay flat on my stomach in order to peer into that hole in order to see any flame??? Thanks for all the tips. Now onto why the AC isnt working. p.s. this image is after I reassembled everything.
You are not the only one… I either use an inspection mirror that has a swivel head or I use a lighter and turn it on without clicking the igniter. It lets gas out and if the pilot light is lit, the lighter will light.
 

Othelzer

Member
Dec 12, 2019
23
California
Great responses, not one error
I'm a mechanic and I only say that to say kudos to everyone for spot-on advice.
Two problems:
Propane
Check for enough propane to sustain the flow of propane at temp ( you can have enough propane to light a fire on the stove but not the refrigerator. It needs 1/8th of a bottle or better.

Vent and combustion chamber clear
That big orange flame was a dead giveaway.
This is a good time to talk about extra fire extinguishers I'm not lying when I say I carry 4 for just this kind of thing.
They don't last long and they are cheap
insurance you only buy once.

Thermocouples fail a lot in refrigerators, water heaters, space heaters and, and heat pumps. When manufacturers could use mercury it worked better but it's dangerous and they outlawed it for civilian applications. And most commercial applications. ( not all, ammonia cycle commercial glycol units)

Propane uses 12 volts to ignite and latch
So there is that check of minimum voltage.
So you should have no less than 11 or it will just not latch. Older units use a thermal probe to latch that cuts gas if no fire is sensed, this probe is attached to pilot light on those units.

The propane burner can supply nearly 1200 btu's the 110-120 volt a/c not so much maybe 5000 btu
Because its limited by the line voltage and current of 15 amps.

So you have to treat it nice to coax it to work, you have to level the refridgerator not the trailer humans can tolerate up to 3 degrees without a issue, the refrigerator has to be dead flat axialy and transversly,
Then you need time , it is pumping the heat out with heated Anhydrous amonia, it sounds crazy but its true and the RV repair club has whole artical on it
https://www.rvrepairclub.com/article/how-absorption-refrigeration-works/
Absorption-Refrigerator.jpg


No matter if its A/C ,D/C or propane
It works this way , the only diffrence is the heat source and its power level to boil amonia

Again propane can have 10-12 thousand BTU
A/C 5 thousand BTU on 1500 watts
And the 12 volt 250 watt 853 btu is a joke but will do the job if you can supply 12 vdc without killing your battery ( mostly used for driving to your campsite)

A/C - 110-120 elements burn out, even more the thermocouples burn out some one with electrical savvy should check out voltage supply, voltage thru the thermocouple fixed temp. And the overtemp sacrificial thermocouple saftey sensor ( we call it switch because its a thermal switch to us mechanics and electrical guys)

Other reading
https://campergrid.com/rv-refrigerator-amps-watts/

I dont know if i helpped i over think.
You can send email at [email protected]
If i left out anything you need.

Coleman / fleetwood westlake from salvage. Recabled ,new water pump next
The door fiberglass section of door panel
 




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