Refrigerator Woes

[Davis]

I ha 1991 34ft trailer with a RM3804 Dometic refrigerator that is not cooling as good as I think it should. Here in South GA we are having ambient temps with lows aound 70deg and highs around 95 deg. with fridge temps in morning at 42 deg and during hot part of day up to 48 deg and not even being opened . When ambient temps are below 85 deg the fridge maintains temps below 40 deg. I have the fridge thermostat on Max. and have a fan in the rear to blow air over coils. The cooling coil was replaced in 2000. Is does not matter if it is on gas or electric.

Is it getting time for another cooling coil replacement or would it b better to replace complete refrigerator ? Thanks for any advice Davis

[ROBERT CROSS]

This has worked for us, cheep too..
RV Refrigerator Circulating Fan on Sale

[richinny]

make sure that the inside of the fridge is level.

does it cool the same on ac or gas? gas is said to heat better. too many items in front of the fins inside the refrigerator will reduce temps.

does the freezer vary temps too?

[lewster]

The air flow has to be across the condenser at the top of the unit, not the absorber coils at the bottom. Also, check your door seals. They might be leaking warm ambient air into the fridge box.

[Jammer]

1) check the door seals

2) be sure the light doesn't stay on when the door closes

3) defrost if it needs it

4) be sure the outdoor airflow is unobstructed from the outside door all the way up the chimney to the roof

[Davis]

Thanks for the replies.

I do have a battery operated fan inside the fridge.

It does not make any difference if it is on gas or electric.

The door seals seam ok and I have pushed on the doors hard to make sure they close completely .
The freezer seems to not go over 5 to 10 deg during the hottest part of the day.
The fridge and trailer are level.
The light is not on while door is closed.
The fan on the outside is 110 volt and does blow air from the bottom up an there is no obsructions .

The only thing that helps is ambient temps below 85 deg.

I have heard in the past that there is too much room behind these refrigerators in the rear of the compartment and does not allow the air to circulate properly therefore resulting in increased heat build up with the rear coils. Is any of that true ?

Thanks for any advice.

[lewster]

Fans are always more efficient when the pull air rather than push it. That said, I have had great success thru many installations of 12VDC computer fans either attached to the 'roof' of the fridge air space or attached to the actual upper grill or roof vent. Note that the orientation of the fans is always blowing out and pull the air up thru the lower vent door and across the condenser fins.

Check you door seals with a dollar bill. Close the bill in the door seal and gently pull it out. There should be a slight drag on the bill. Do this all around both doors. If you have a spot that pulls easily, you have an air leak and need a gasket kit (if available, which they ARE NOT for most fridges) or believe it or not, new doors!!! Sometimes you can get behind the door seal and shim it out with foam for a tighter fit.

These work equally as well on side vent as well as roof vent refers. For a roof vent application, place the fans either right on top of the screen found when you remove the roof vent cover, or just beneath the screen.

Try it and you'll see the difference. BTW, the Dometic spec is 34-42*F in the refer and 10-15*F in the freezer. Remember, these are gas/absorption units and NOT compressor driven units and are in no way as efficient. RV soft serve anyone???????

[Davis]

Thanks Lewster,
I will try the dollar bill and see if there is any problems there. I will have to order a fan to mount on the roofvent area. I just don`t like the fridge temps to be around 48 deg and up that is not safe for potentially hazadous food such as meat,eggs ect.. I manage a restaurant and I am very conscious of fridge/freezer temps. Thanks Davis

[Davis]

I tried the dollar bill technique and there was drag on it all around the doors.
So I will have to order a fan kit and install on the upper coil/vent to draw air out.
If you think of anything else let me know . Thanks Davis

[3 Dog Nite]

Be sure that the inside air can circulate in the fridge. If it is packed full, the cold air produced can't get around. Square bowls/boxes put into corners are a big no-no.
I also recommend a fan. Right now I have a regular 10" fan sitting on the bottom of the rear fridge area. It blows up & has made a diiference in the last week since its been there. I will be putting in the smaller computer type fans with a thermostat when time/$$$ allows. I live in TN & faced the same weather you are describing. Plus the fridge side is in direct sunlight for 11 hrs a day.

Ricky

[Davis]

Finally got around to installing a thermostatically controlled fan in the fridge roof vent today. So hope this helps. Will keep you posted.

[mello mike]

A fan in the refrigerator vent should do the trick. It worked in our '72 Sovereign.

[mikeandnora]

I have a couple pc fans laying around.


Do you get 12v from back of fridge connections or elsewhere?

[Inland RV Center, In]

The hotter the condensing coil at the top, the less efficient the reefer becomes.

The heat is worst when the sun is out.

Instead of a 12 volt powered fan, how about a "solar powered" fan.

That way when the sun is out, the fan runs, the condensing coil stays cooler, the reefer works better.

And when the sun is not out, the issue is gone.

Just think, nothing to turn on or off, but works all by itself from the sun.

Andy

[Silver Goose]

Originally Posted by Davis

...I have heard in the past that there is too much room behind these refrigerators in the rear of the compartment and does not allow the air to circulate properly therefore resulting in increased heat build up with the rear coils. Is any of that true ? Thanks for any advice.

I recall seeing that in an installation manual, particularly for the area behind the coils. What I understood was a space of only a couple inches forms a Venturi of sorts that channels the airflow across the coils. The exterior wall behind my fridge was boxed in so while the fridge sits nearly a foot away from the wall, I can barely put my hand between the coils and this boxed in section.

Placement of a fan that assists the chimney effect and creates additional airflow across the coils can improve the efficiency of the fridge.

Proper loading of the contents in the fridge to allow cold air circulation also helps and many have found a supplemental fan in the fridge to be beneficial.

My question would be: Do you know if this fridge has always preformed this way, or is this a recent development?

[DKB_SATX]

Originally Posted by mikeandnora

I have a couple pc fans laying around.


Do you get 12v from back of fridge connections or elsewhere?

Unless Mello Mike has a refer newer than his trailer, his doesn't need 12V. Our older refers are just 120V and propane, with no 12V control board and no electronic ignitor for the propane. It's a bit more fiddly, but also a bit more reliable since one of the most common complaints I read about with fancier refer units is dead control boards.

[masseyfarm]

This is a refinement of a number of ideas and seems to work great.

http://www.airforums.com/forums/f313...ml#post1010868

Computer fans are cheap, and if run off solar without a battery, will run at varied speeds depending on the sun, and are quieter at lower speeds. 12V then when you need it.
Dave

[mello mike]

Originally Posted by DKB_SATX

Unless Mello Mike has a refer newer than his trailer, his doesn't need 12V. Our older refers are just 120V and propane, with no 12V control board and no electronic ignitor for the propane. It's a bit more fiddly, but also a bit more reliable since one of the most common complaints I read about with fancier refer units is dead control boards.

I have a new refrigerator in my '72, a Norcold I bought back in 2006. It does require 12v to operate and that's how my tiny computer fan is hooked up.

[Davis]

Originally Posted by YankeeDoodle

I recall seeing that in an installation manual, particularly for the area behind the coils. What I understood was a space of only a couple inches forms a Venturi of sorts that channels the airflow across the coils. The exterior wall behind my fridge was boxed in so while the fridge sits nearly a foot away from the wall, I can barely put my hand between the coils and this boxed in section.

Placement of a fan that assists the chimney effect and creates additional airflow across the coils can improve the efficiency of the fridge.

Proper loading of the contents in the fridge to allow cold air circulation also helps and many have found a supplemental fan in the fridge to be beneficial.

My question would be: Do you know if this fridge has always preformed this way, or is this a recent development?

As long as I have had this trailer for the past 8 years it has been an issue but it seems worse this year due to the extreme temps. I do know that other Airstreamers have experienced this as well and especially with the 34ft trailers. I have even seen people leave the access door open and prop box fans to try and make there fridge cool better. But when I talk with other X brand owners they dont seem to have any problems with there refrigerators.

[Davis]

I have installed a roof vent fan that is thermostically controlled and that helps but still not enough.

I had originally had a D cell operated fan in the fridge box . So I purchased a dual fan unit that is 12 volt and hooked it up to my interior light and it attatches to the cooling fins via alligator clip that also acts as a ground. That helped the most instead of seeing temps in the 48 deg and up now I am seeind 42 deg at the peek part of the day when it is 95 and up outside. The dual fan unit really moves the air. I found this on Ebay.