Vent refrigerator with cool inside air?

[wopachop]

Have a dometic fridge located in the middle of the trailer. Underneath is a 4x10 intake vent with the exhaust coming out the roof.

We are not of sane mind and go camping in temps that can reach 120F. The fridge really struggles. The AC runs constantly and i suppose the cabin gets down to 80s or 90s.

I can access the refer intake duct by removing the electrical panel. There is also a 4" heating duct that i have abandoned.

Thinking about using the 4' opening with a small computer fan to blow cool air into the fridge duct. With a baffle maybe to close it off. Or just a vent cover that can close.

On the summer camping trips i would just tape off the the vent under the trailer, and turn the fan on.

What do you think?

[DougE]

Refrigerators with 12v compressors, used in big rigs, are available from Truckfridge.com. Some models come with automatic 120v/12v switch over.

[landyacht318]

If burning propane I would NOT allow it to suck cool interior air, as the system should be closed and not allow any by products of combustion to enter the living space, and while heat rises and should not be able to backtrack, neither is the world perfect.

This is one case where I would prefer more fans up high, and ensure all the Air they move is being dragged across the coils, and that they are not able to pull air through any other cracks.

Proper baffling and fans up high to suck even more air across the coils would be my personal ideal, although I know it is likely easier to aim fans at the coils from below.

I do not think huge volumes of air exchange are required to greatly aid cooling of an absorption fridge in hot weater.

If the AbS fridge is on the sunny side, perhaps have the intake below the rig instead of on the sunny side.

I'd not replace it with a resdential unit while it is still working fin in less than blistering temps. Only if it does not respond as desired to increased airflow across the back.

DC compressor fridges do kick some Heiny in the efficiency department though. Low start up surge, no inverter required, but they are $$$$.

[TechWriter]

wopachop wrote:

Thinking about using the 4' opening with a small computer fan to blow cool air into the fridge duct. With a baffle maybe to close it off. Or just a vent cover that can close.

I did something similar with my Class A's residential fridge.

I got the idea when I was camped in a Texas campground for a month. The fridge side of my RV got the full force of the sun most of the day and the fridge temp increased towards 40 degrees during that time. BTW, I monitor my fridge temps.

So I cut a hole behind my fridge that led into the RV and added some fans in the old fridge roof vent. Now cool inside air flowed up behind my fridge and out through the roof.

Worked like a charm.

[GordonThree]

fridge shouldn't be generating any propane fumes (carbon monoxide) while it's running on electric.

[wopachop]

Thats good to hear youre able to handle 108F. Was watching another video and the guy added fans to his vents. Also had a thermostat. He said through testing other RV enthusiasts found that 130F at the exhaust is a good temp to start the fans.

Promising to hear that lots of airflow might be able to combat high ambient temps.

[doxiemom11]

We were having the same problem here in NM - we added a small computer fan at the bottom of outside compartment blowing upward and it made enough difference the refrigerator stays around 34 degrees now. Our high has only been 108 though and we do have our awning out to shade that side from the morning sun. No option to park a different direction in this park. All sites face the same direction. Morning sun better than afternoon.

[wopachop]

Is that common to switch to a residential fridge? In my brief amount of time learning about RV absorption refers i thought theyre made of steel, no moving parts, and better suited to bounce down the highway compared to a residential fridge.

Any chance someone has a basic spec for how much air would naturally flow through the vents using convention only? I dont have to use a fan. Could vent to the cabin and let it flow naturally. Whats the deal is that a propane hazard? Probably so. Trailer has a propane detector. Should test it with a weed burner.

Or maybe its better to mount a stronger fan outside the rig. Will be blowing 110F+ air, but lots more of it. Will try that method first before cutting into the duct. If we are out there and fridge cant stay below 40F then i might tin snip a hole right there while camping.

[beemerphile1]

Doing what you propose would also open the RV to potential fumes entering.

[GordonThree]

Draining cold air from the cabin isn't going to last long. As you create negative pressure inside hot air is going to be drawn in to replace it.

Switch to a residential fridge, a low power DC fridge, or just move a higher volume of air over the cooling coils.

[MrWizard]

A/C is constantly on
so you are on shore power

IMO the best option is replace the fridge with a residential
120v compressor fridge will work better, and you can block off the both outside vents, intake and roof, and vent/circulate inside the RV

[rexlion]

Why not replace the fridge with a dc model that has a danfoss (secop) compressor, add another battery and some solar panels? It will hold the cool setting way better.

[wopachop]

Been watching videos. Especially from the Ford Rv AC people on youtube. He says the ambient air temp really effects the cooling ability of the fridge.

For extreme cases like camping in 120F i think venting with the inside air should really help. Next trip isnt until July. Will post up the results.

[MrWizard]

might help
but remember all the air being exhausted
will be replaced by hot air from outside coming into the RV
which will make the inside of the RV warmer
how much ? IDK, but its plain physics

[GordonThree]

Just adding fans to the existing fridge vent should do the trick, without having to use your cool inside air.

The hot outside air doesn't circulate through the coils as well as cold air does. Since the air is already hot going in, it doesn't get much lift being heated by the fridge coils, in order to vent out the roof.

Adding some computer fans blowing out the roof vent should help that convection do its thing. Look for high static pressure fans, their blade design works better to move air through the roof vent.