How to tell if Dometic Refridgerator is working ?

[bcraig]

I have a 1989 20 ft Fleetwood Prowler Lynx travel trailer.

The camper has a Dometic RM 2501 Refrigerator.

I am testing everything in the camper

I hooked up to workshop and tried it using the electric Mode
The flue bottom of the flue was getting warm.

Then I tried it using the Gas mode and got auto igniter sparking and then it lit.

I am not familiar with Fridge operation and dont know how to tell if it is working properly !
I cannot hear anything running nor does it seem any cooler after an hour or so of being on.

How can I tell if it is working properly? Which part of the fridge do I need to feel to see? Does it cool off from the bottom up or from the top down?
How long should it take to be able to tell if it is cooling properly?

Thanks
Craig

 

[rvpuller]

Cools from the top down, you have to give it some to start the process like maybe 6 hours.

Denny

 

[Arch Hoagland]

You probably won't hear anything.

I turn my Norcold refrigerator on 24 hours before I want to use it. They don't get cold very fast.

I keep a thermometer in mine and it will usually cool to about 38 degrees in 24 hours based on what temperature I set it to.

 

[Lou Schneider]

An absorption refrigerator uses heat to boil an ammonia and water mixture, then the ammonia gas rises via convection and flows through the cooling coils in the freezer compartment at the top of the refrigerator.  It cools as it condenses back into liquid form.  You won't hear much if any sound when it's running, certainly not like a compressor driven refrigerator.

You should feel the freezer compartment walls and floor start to get cold within a half hour or so after you turn on the refrigerator.  Full cooling can take 8 hours or as much as full day.  Once the box is cold, the refrigerator does a good job of keeping it cold.

Make sure the fridge is level whenever you're using it.  It relies on convection and gravity to keep the refrigerant flowing, and the boiler can run dry if it's more than just a little bit off level.  Driving down the road there's enough motion to keep things flowing, but they really don't like to operate off level when sitting still.

Here's a link to the manual for your refrigerator:

http://bryantrv.com/docs2/docs/operating/rm2401.pdf

 

[bcraig]

The Fridge got nice and cold when on AC current .

When Testing to see how well the fridge works on Propane and Just the House battery should I first get the fridge cold with ac current
with either shore Power or the generator ??

Thanks
Craig

 

[Scott 3]

I hung a small thermometer inside so I know not only if it's running but if the temp is in a safe zone.  Seeing the temp gives me piece of mind.

 

[Arch Hoagland]

The Fridge got nice and cold when on AC current .

When Testing to see how well the fridge works on Propane and Just the House battery should I first get the fridge cold with ac current
with either shore Power or the generator ??

Thanks
Craig

No that's not necessary, either one is fine.

I've done it both ways although I tend to use electric when possible to conserve on propane.

 

[Lou Schneider]

The Fridge got nice and cold when on AC current .

When Testing to see how well the fridge works on Propane and Just the House battery should I first get the fridge cold with ac current
with either shore Power or the generator?

The refrigerator should get and stay cold equally well on either source.  Make sure they both work ... electric heating elements can burn out, the flame's heat can be blocked by an obstructed flue.  It would suck to have a refrigerator full of food and switch to a mode that doesn't work.

 

[bcraig]

Well The fridge works on Propane as well although it seemed to be colder on AC current than Gas and DC .

Inside the freezer section it was VERY Cold and the bottom of the fridge was cool but not cold.

Of course I did the main testing of the fridge on AC about 20 degrees cooler last night than it is right now doing the testing on DC and Gas.
I presume that might make a difference ?

How do I check for an obstructed Flue??

 

[kdbgoat]

To get a good temp reading on the fridge part, place your thermometer in a small glass of water. If the thermometer is in open air, the reading will skyrocket as soon as you open the door. The thermometer in the glass of water will give you a good reading.

 

[grashley]

Since the propane worked well, your flu is not obstructed.  That can change quickly.  A spider web and dust is an obstruction.  Others smarter than me can tell you how to clean it when needed.

Also, note that 12V power is ALWAYS needed for the fridge, water heater or furnace to operate.  The 12V can come from a battery or from a 120V / converter.  This 12V power runs the electronic circuit board that monitors temps and turns on power for A/C for the appliance, or turns on the propane valve and ignites the flame.  It also verifies the flame is lit and stays lit or it shuts things down.

 

[Honorbuilt22]

Hi guys!

I wanted to add on to this question, since I'm working on a similar issue.

I took my new second hand RV camping for 10 days and the fridge didn't work - it might've been a couple degrees cooler than the outside air, but not enough to save our food! We were running it off propane.

Last night I tried running it off the 12V battery and that didn't seem to work.

I've just plugged it in directly to an outlet and changed the setting to "Electric" and the freezer part is getting cold, so there is some life there.

Any advice as to how I might be able to make it run off propane and/or the battery? I really want to feel the sense of satisfaction in fixing it myself and learning about it!

Any light you could shed on the matter would be greatly appreciated!
Thank you!

 

[Larry N.]

I wanted to add on to this question, since I'm working on a similar issue.

Two suggestions: Start your own topic, rather than using a year-old topic. It'll probably get better results. And Let us know what your rig is, and what refrigerator you have. Though some RVs have a 3-way fridge (12V, 110V, LP gas) most don't, and there are a lot of different fridge models out there, most by either Dometic or Norcold, but some occasional others as well.

With that out of the way, running a fridge on 12V DC uses a LOT of battery in a hurry, and is generally intended for the time you are driving while the vehicle generator is supplying power. It can run batteries down in a hurry. And typical RV fridges can take up to 24 hours to really get cold. Also, you should keep the RV pretty much level when parked, in order to avoid damage from overheating parts of the mechanism.

If you unplug shore power or unplug the fridge from the wall outlet, and if you have your LP tank turned on, it should switch to propane, IF you have the Elect/auto switch in auto position -- or maybe yours is set up differently, so let us know what you have.