Refrigerator

Refrigerator will only run on electricity will not get cold on gas.  Looking for help.  Cleaned out burner tube, replaced  thermaster, & circuit board

The obvious first question... I presume you have propane in the tank and the valve on the saddle tank is open.  I also presume you have the refrigerator set for auto switch from gas to electric and that you are not hooked into shore power (while you are testing).
Remove the bottom vent cover on the outside.  Have someone listening outside while you turn the refrigerator on,set it to it's coldest setting. Do they hear a snapping noise?  That is the spark ignighter for the propane.  If they don't hear a snapping, the ignitor isn't working.  Make sure it's wired properly to the main circuit board.   Next, if they do hear the ignighter snapping, can they see a flame in the burner tube?  If so, the refrigerator should start cooling.  If no flame, then the regulator solenoid isn't opening the propane line OR the line is full of air.  Let it sit for about 10 minutes to allow the propane to purge any air in the propane line.  The ignitor will snap for about 5 seconds and shut off, 30 seconds to a minute later, it should start snapping again and so forth.  If that doesn't turn the flame on, your regulator wiring or the regulator itself needs checked.   That's all one unit that replacement is best left to experienced RV technicians unless you are VERY confident in your propane plumbing skills.

The propane side of the refrigerator works as it should in that it is in auto mode. When on electric it works 100%. When it is changed to propane it ignites as it should . Good flame, all blue, looks strong but i ran it on electric and it was 35 degrees in the evening. Changed over to propane and by morning it was 57 degrees. Cannot use my new coach as we cannot keep food in the refrigerator.  Very disappointed.???

Your registered name and so forth show this is a 2016 2400 that you bought in March.  New for you, but not factory new.

From your posting I presumed you were not getting a flame.  So you are getting a flame but not enough cooling.

The electric heater and the gas burner heat the same liquid in the cooling system.   My advise would be to have a Norcold tech look at it.

I also have a 2016 model with a Norcold refrigerator.  I see you are from the West.  Depending on the elevation you may experience cooling issues.  Norcold states in the manual the refrigerator should be operated on electricity above 5500 ft.  I have operated above that on propane and noticed some deterioration in performance.   I think there is a good bit of variability from unit to unit on how they perform at higher elevations.  Since you say it operates ok on electricity but not propane it basically has to be due to inadequate heat being delivered by the propane.  Obviously there are several things that can cause that but it appears you have already addressed the major ones.


You said you had  cleaned the burner tube, if you haven’t already you should carefully clean the burner jet as well.  A proper clean flame is important at any elevation but especially so at higher elevations.  Proper gas regulator pressure potentially could also be a contributor as well.  This should also be checked.


If your inadequate cooling is indeed related to elevation then this is another disadvantage of of a propane absorption cycle refrigerator when compared to a 12 volt compressor style unit.

I also have a 2016 model with a Norcold refrigerator.  I see you are from the West.  Depending on the elevation you may experience cooling issues.  Norcold states in the manual the refrigerator should be operated on electricity above 5500 ft.  I have operated above that on propane and noticed some deterioration in performance.   I think there is a good bit of variability from unit to unit on how they perform at higher elevations.  Since you say it operates ok on electricity but not propane it basically has to be due to inadequate heat being delivered by the propane.  Obviously there are several things that can cause that but it appears you have already addressed the major ones.


You said you had  cleaned the burner tube, if you haven’t already you should carefully clean the burner jet as well.  A proper clean flame is important at any elevation but especially so at higher elevations.  Proper gas regulator pressure potentially could also be a contributor as well.  This should also be checked.


If your inadequate cooling is indeed related to elevation then this is another disadvantage of of a propane absorption cycle refrigerator when compared to a 12 volt compressor style unit.

Thank you!! I appreciate your advice. My elevation here in Montana is 2380. Don't feel that should be a issue. I also seem to have a very clean flame. ?? I don't know if i should just buy a new refrigerator.  Not sure about how to physically change it??

I have had just the cooling unit changed in 2000 Winnebago Minnie.  It was a recall so the Norcold service folks removed, replaced the cooling unit and installed the refrigerator.   It was a heck of a job to get out because Winnebago literally coated the bottom of the refrigerator with rubber adhesive to keep it from rattling.   No idea on how Phoenix holds them in place.

Again, I would at least take it to a shop to let them see what may be wrong.

BTW, I have run my 2015 Phoenix at 10,000 feet here in Colorado on propane with no problems.  Ran the generator during the day to recharge batteries (no shore power there) but evenings and overnight was all via propane for heating and refrigerator.

Doug,

You may have already read my comment on my repair of my own refrigerator in the recent thread titled "Refrigerator Vent Fans".  My symptoms were identical--fridge cooling great on any electric source, but not on propane.  Since I had no prior experience at all with this type of refrigerator, I had to do substantial research to understand enough about how it worked to try to troubleshoot it.  One key point is the one that both DONC13 and FANDJ made:  the basic refrigeration cycle is the same, and uses most of the same components, for both electric and gas operation--the only difference is the method of heating the ammonia/water mixture in the boiler.  On electric the boiler is heated by a heating element and on gas it's heated by the flame.  If the unit works fine on electric, your basic refrigeration cycle is working properly, and most likely you're just not getting enough heat from the burner flame.

In my case I also thought my burner flame looked pretty good--but I didn't have any experience (other than a YouTube video) to judge that.  I did note that my condenser coil located at my upper vent was just warm at the inlet operating on propane, but got too hot to touch when on electric.  What I finally found was that the vent pipe that exhausts the heat and gas from the flame was partially blocked internally at the top by a dirt dauber mud nest.  It wasn't totally blocked, but was obstructing the natural gas and heat flow up through that vent pipe enough that it was not letting it heat like it should.  As soon as I cleaned out the obstruction--although I didn't notice a huge difference in the look of the flame--I got a lot more heat coming up through the exhaust pipe, my condenser got much hotter at the inlet, and the fridge cooled back down to normal (about 35F).

A couple of take-a-ways from my experience is that other things besides just the flame can compromise effective heating, and the flame can look pretty good (at least to an untrained eye) and still not be transferring enough heat to the boiler.  Also, a good way to compare heating effectiveness is check the heat at the tube going into the condenser.  Switching between electric and gas, I could tell a marked difference before I corrected mine.

Thank you so much for your information. I think I might have the same problem with a blockage from a mud robber or ?. How did you clean out your blockage?
Thank you again

Thank you so much for your information. I think I might have the same problem with a blockage from a mud robber or ?. How did you clean out your blockage?
Thank you again

Doug, I have a model 2552, so my refrigerator is in the slide--with upper and lower side vents for the fridge.  In my case, when I pull off the upper side vent cover, immediately inside is a thin plywood baffle installed by Phoenix to direct the cooling air in the vent column through the condenser (rather than the air flow bypassing it).  When I pull out that plywood baffle, the upper exhaust pipe from the gas flue is right in front of me--it's about 3" in diameter and had a little push on flat deflector cap on top of it that leaves maybe an inch of space around the side for the flue gas to escape.  I initially didn't know there was a blockage inside or that the cap was removable, so was looking for something flexible I could work through that inch gap and run down the flue pipe and settled on a length of stiff electrical wire.  Of course my first effort found a gap and missed the mud dauber nest, so I was able to run the wire all the way down to the boiler chamber where the burner is.  In the process however, I dislodged the deflector cap, realized it was removable, and pulled it off.  I was then able to get my head just enough inside the vent housing to see a little way down the flue with a light and saw part of the mud ball about 2-3 inches down the vent pipe.  Then I just had to work some short screwdrivers and stuff down inside to break the dauber nest up and used a shop vac to suck up the debris (and also what fell down into the burner).

I don't know how likely that you have the same problem, but as I said in my earlier post what I learned is that the gas flame heating is pretty sensitive to any type of issue (even when the flame itself looks "pretty" good).  I could tell a difference in my flame after I opened up the vent--but not by as much as you'd think--there was a big difference in the effectiveness of the heating however.  Whether it be a vent obstruction, a burner or gas jet issue, or other--I think everything has to be pretty "right" for the propane part of the fridge to work.  That's probably the reason that Norcold warns about possible high elevation effect on heating--as the air thins out, the water/ammonia mixture boils at a lower temperature and consequently the boiled vapor carries less heat.  The propane part of the fridge doesn't have as much extra capacity to heat the mixture as the electric element does, so cooling suffers on propane first.  From your symptoms, you have a heating deficiency from some cause--just have to find it!

Thank you for your reply. Glad you found your problem. My Cruiser is a model 2400. It is not in a slide so I don't have a upper vent but i do have a roof vent. Using your info I think I might remove my roof vent and see if I can look down then vent tube? Now my only problem is I am a handicapped senior so getting to my vent might pose quite a site. lol  I live remote in Montana so it is quite a trip to a dealer for help. That is why I have been trying to fix this on my own. I really do appreciate your help. Thank you again!

I started this discussion inquiring if anybody had ever installed the Titan refrigerator vent fans.    After reviewing Mikeh's post and receiving a private message I have decided, at this time, not to install the Titan refrigerator vent fans.  We have a 2017 - 2910 D where the refrigerator is not in a slide and the vent is on the roof.   What I have learned is a fan is probably necessary where the refrigerator is in the slide.  It makes sense that if the refrigerator is not in a slide and there is a roof vent heat escapes more easily.    When we have been on longer RV trips (longest being 6-7 weeks) we have not had any issues with our refrigerator.   But, as explained by Mikeh, it's very important to have the rig level for maximal efficiency and if using propane there must not be any obstruction. i.e mud daubers....  At least for now I am not going to install any vent fans

Dave
2017-2910D

This is just more info about my refrigerator that still will not work on propane but works 100% on electric. I turned the refrigerator on propane without pre chilling it on electric  and found that the refrigerator part will not work on propane but the freezer does! I really need to find out what is wrong with this refrigerator and am hoping maybe this new information will lead to a solution. If anybody has any information on this problem,  I really need some help. Thank you

.....found that the refrigerator part will not work on propane but the freezer does.....

Click on the links below.  Maybe something in there will trigger an idea.

https://www.rvingknowhow.com/rv-refrigerator-not-cooling-but-freezer-is/

https://camperadvise.com/rv-refrigerator-not-cooling-but-freezer-is/

Presuming it's a Norcold, there's really only 1 cooling unit and that's the freezer.  The fins in the back of the refrigerator are attached to the freezer where the actual cooling coils are.

There should be a "clip on" sensor on those fins on the right side (looking in) that are used to regulate the temperature inside the refrigerator section.   If you don't have the original manual, you can go to

https://norcold.com/product-manuals/

and get the manual for your model and read the troubleshooting section.