Dometic fridge not staying cold when outside heats up

[Twotravelers]

The dometic refrigerator in our 2016 Flying Cloud 28 doesn’t stay cold when the temps outside are in the 80s or more. We have a unit-long window awning on that side of the trailer to keep it shaded.

Today it was 35 at 1:36 and is up to 38 now—3:50 pm. Outside temp is 85 and the fridge has only been opened maybe 3 times during that period. Last night the temperature went up to 44 and is was still only 42 at midnight. The outside temp was in the 70s.

Those aren’t safe temps to keep food. The fridge isn’t empty but it isn’t packed full, either. We have been traveling for 2 months and it just gets worse and worse. We do have a fan inside to keep the air moving.

What can we do?

[SilverHouseDreams]

Does your unit have any fans in the outside part to help circulate air around the external heat exchanger? I have seen mods on here where people add fans, you might try doing a search for it.

[uncle_bob]

Hi

First question - are you on propane or on electric?

Second - does it have the problem on *both* propane and electric?

If it's only one and not the other there are troubleshooting processes for each. Propane involves checking the flue and burner for crud / dead stuff. Electric involves checking wiring and breakers.

If it's both then ventilation is the first thing on the list. Same issue about dead stuff / crud. Next you are off to check control boards. If that's not it, the magic ammonia system may have sprung a leak. Yellow stains are a pretty good indication of that.

Bob

[OTRA15]

Sorry for your troubles!

If possible, you can put bags of ice in the fridge/freezer to keep the food safe. We always carry extra ice in a cooler in the tow vehicle. This is a temporary solution obviously, and you will have to manage the water which melts off.

Please provide more details such as answers to these questions:

Have you read your owner’s manual
Propane or electric cooling
Fan in fridge mechanical space to aid in cooling
[not your fan inside]
[switch for fan or just thermostat]
Thermistor to adjust on cooling fins inside
Temp adjustment on fridge control panel
Flue through roof to exhaust hot air from mechanical space
Etc.

Please provide as much info as you can, in addition to that requested in the other recent posts, and we can probably figure this out.

Peter

PS the new search function in the blue box above works great. Will post search results from laptop later.

[Tsunami-v2]

When the temps outside rise, we take a tupperware container and fill it with ice and set it in the back on the bottom shelf of the frig and it assists keeping the temps down. The container was 8" square and 6" high. Worked like a charm. We changed the ice out every couple of days. Does your refrig vent thru the roof or does it have a second louvered opening located directly above the lower opening?

[TBRich]

I think Uncle_Bob had good questions about whether this is happening on electric or gas or both... good place to start with trouble shooting.

I am of the opinion that you should not have to use extra ice in your refrigerator compartment in order to have a cold fridge. It should maintain cold temps on its own.

If yours is not doing that to your satisfaction, you should have it looked at.

That said, a fan to circulate the air inside the fridge is a good thing. And an exhaust fan in your outside fridge compartment would be helpful too.

Good luck!

[OTRA15]

Twotravelers, here is your owner's manual I think:

https://www.airstream.com/wp-content...ying-Cloud.pdf

On p. 5-16 [PDF p.46/112] is the fridge section. On the top right of that page under Operation, it says: "On all other models, refrigerators vent through the roof and do not require a fan," so you should look on the roof above the fridge for a aerodynamically curved vent cover over the flue. There is no fan apparently to exhaust air from the mechanical space behind the fridge. You could get up on a ladder to make sure that hot air is coming out of that flue roof vent, but be careful because the entire structure may be too hot to touch. If no hot air is coming out, your flue might be clogged in some way. Has the fridge been off for a long time before this trip? Make sure there are no birds' nests up there. Our old flue cover had plenty of room for nests FWIW.

If you have a thermistor which you can slide on the cooling fins inside the fridge, slide it up for colder. [mnemonic: it is colder UP north ] The manual is silent on the thermistor, but your Dometic manual may have something on this. You could also put "thermistor" in the blue search box above to see other posts on-topic.

Here are some search results which may help:

https://www.google.com/search?q=28%2...=airforums.com

One suggestion I just saw says to turn off the fridge and turn it back on. It may reset in a beneficial way.

Another factoid to post, in addition to the questions in Post #2, is your battery voltage, has it been consistently above 12.2 volts?

Please fill in as many missing details as you can. Don't worry about this, it is why we all own Airstreams -- to tinker with them!



Thanks,

Peter

[A W Warn]

OTRA 15 has it right
this video shows how to make it colder

https://www.youtube.com/watch?v=zKxyHkp61jg

[Twotravelers]

We put in containers of ice last night and the unit cooled down nicely. Thanks. Hopefully, this won’t be something we have to do continually, but glad our food is now safe.

[Twotravelers]

Thanks for the input. We will check the roof vent as soon as we can get up there.

[OTRA15]

Thanks for the updates. Our fridges are actually fairly well-insulated rectangular boxes, so they are basically the same as regular portable coolers, when you add ice. Hard to get the freezer to keep ice cream solid, though!

[kb7our]

Originally Posted by Twotravelers

Thanks for the input. We will check the roof vent as soon as we can get up there.

Roof vent is fairly easy to check even with a short 5' ladder. We have a 28 and have approached this issue from 3 fronts: 1) Moved the thermistor up, 2) added fans behind the access door to push air up through the roof vent, and 3) added an interior fan kit. In combination, this has helped keep temps within reasonably normal range in hotter climates.

[OTRA15]

Great feedback, thanks!

[guskmg]

If you wind up needing a cooling unit call Wick at 1-800-515-6823. His webbsite is <rvcool.com>. He is an independent rebuilder of Dometic Cooling units. He rebulds the units with a much improved swirling system in the coils. All tubing will be new. In 2015, when he did mine, I asked him how many come backs he had and the answere was "0" in 19 years of business. He does R&R at his shop, but will ship anywhere with exchange. I can't believe how mine performs now.
guskmg

[leif9016]

I had the same problem but my fridge is the original 1984 unit that came in my Sovereign. I pulled it out because I heard that when they sit unused ( mine sat for 15 years!) They build up crystals and blockages in the passages. I turned it upside down for a week then flipped it back. Yours being newer you probably don't have that problem but when it was out I noticed the fins on the outside back were covered with dust. I cleaned them with compressed air and reinstalled. Now I have 38 degrees at 5 rather than 50 degrees on Max. My next plan is to install a couple computer fans on the back aiming upward at those coils with an 85 degree disc thermostat switch. Got the fans and switch off eBay for $15

[accordionman]

We have been having the same problem on our classic. On our last trip to Topsail State Park in FL about two weeks ago the outside temps were in the high 90's. Our dometic consistently went up into the high 40's. I had already put a fan in the outer compartment to help vent air out the top of the roof, but that has not helped at all. When we arrived home, I ordered some small ice packs and a battery operated fan for the interior on the next trip. I'm really at my wits end with this thing. Some things that I have already tried and notes:
1. it cools identically on prop and shore power
2. I have turned the unit off/on a number of times.
Interestingly the fridge cools wonderfully when we bring the coach home to pack for the trip, the temp will go down to 36. There are no yellow powder stains in the back outside compartment and no smell of ammonia, so I believe it's operating properly. I'm hoping that that the interior fan and ice packs help a bit. We've had our coach for just about a yr now and this has happened on every trip that we have taken. The cooler the outdoor temps, the less severe, but happens nonetheless.

[thiel]

I find that if I open the cabinet under the fridge it helps a little, but I do not have the magnitude of issues you are citing. Mine might jump to 44 for an hour or two if we are in and out of there a lot on a 90 degree day.

[Vlamgat]

Are you sure the unit is level. Not just for AS? One degree makes a difference.

[OTRA15]

Originally Posted by Vlamgat

Are you sure the unit is level. Not just for AS? One degree makes a difference.

This might have been true for much older AS, but is no longer. As long as the trailer "feels" level as you walk through it, that is all you need. You might want to confirm in your owner's manual.

[A W Warn]

Level is still important. Read here why>
https://www.rvcool.com/Why_cooling_units_fail.htm