Refrigerator Compartment Ventilation

[For Wheelin]

Is it typical for the compartment where the refrigerator is installed to have an exhaust fan running to provide active ventilation within that compartment?

The dealer re-installed this exhaust fan after replacing under warranty, our Dometic refrigerator.

They first connected straight 12 vdc power so it would run constant?on or off!  I didn?t think that was correct so I requested it be connected to a thermostat of some sort to control the fan to only come on when the compartment becomes too hot to be safe.  They said it must have been wired wrong, and was supposed to be installed to follow the on/off switch of the fridge.  I had to drive it back to them to fix that mistake. 

Then they did install a thermister (??) on a fin of the upper coil (condense or evaporator, I forget) and said even when the fridge is turned off the fan will run until these fins are cooled to whatever point the thermister is..I would imagine what 100 degrees...?  He did not remember exactly what value that thermistor is.

There are both an upper and lower vented access on the exterior, so ventilation is pretty good. 

Still need an exhaust fan to keep it cooler? 

Will that actually help the fridge run more efficiently?

I?m confused!

 

[vermilye]

One of the reasons a fan may be necessary whether there is sufficient natural air flow over the rear of the refrigerator.  Check Dometic Venting Requirements for some interesting information...

 

[For Wheelin]

Actually there is a venting req sticker on the rear of the fridge, I will check it out.

Might running this fan be causing the condensation on the alluminum fins on the inside of the fridge?  Also, there is a drain hose that connects the interior of the fridge to the exterior.

 

[Lou Schneider]

Condensation on the inside fins means the fridge is working normally.  The refrigerant cools the fins, then air passing over them by convection cools the interior.  Since the fins are the coldest point in the interior, condensation forms there first.

 

[Smitty77]

On our 'other brand' 1200 model, when we replaced the cooling unit with the Amish unit. We augmented the stock fans with three othe fans. One is a quiet pancake computer fan mounted very low pointing up over the coils, that runs when the fridge is on. Second is another low mounted fan of the same kind, that I switch on when  I feel the unit is working in a very hot weather condition. The third is a solar power fridge vent cover, that runs during the day.

We have the SS30 extinguisher and a rear cabinet smoke detector.

Much of this is overkill, but we feel the unit is safe, and cools very well. We also wanted to retain LP.

Best,
Smitty

 

[For Wheelin]

I thought condensation on the inside meant outside air is getting in, like a bad door seal or something...If it's normal, ok.  That may explain why they ran the condensate drain through the access door so it would drain outside.  I just don't recall seeing these on our travel trailers owned over the years.


Smitty, that's a lot of fans...   you mentioned a quiet pancake fan...maybe the fan installed in our coach happens to be a really loud and annoying fan.  I think I will go to Fry's and get a high volume quiet fan.  That will give me a chance to fix the wiring they did to install this thing anyway...It's pathetic, various wire lengths spliced together to get through the compartment and it's connections, not at all what I would expect from this particular dealer. 

Thanks guys,

Steve

 

[Lou Schneider]

I thought condensation on the inside meant outside air is getting in, like a bad door seal or something...If it's normal, ok.

It depends on where you are, and how much condensation you're seeing.  Some is normal if there's any humidity in the air.  Every time you open the door you get a box full of outside air, when it cools the moisture has to go somewhere.

If you want to test the door seals, close the door on a dollar bill and see if it holds or if it slips out.  Do this at several different locations around the door.

 

[1Sammiedog]

Is it typical for the compartment where the refrigerator is installed to have an exhaust fan running to provide active ventilation within that compartment?

The dealer re-installed this exhaust fan after replacing under warranty, our Dometic refrigerator.

They first connected straight 12 vdc power so it would run constant?on or off!  I didn?t think that was correct so I requested it be connected to a thermostat of some sort to control the fan to only come on when the compartment becomes too hot to be safe.  They said it must have been wired wrong, and was supposed to be installed to follow the on/off switch of the fridge.  I had to drive it back to them to fix that mistake. 

Then they did install a thermister (??) on a fin of the upper coil (condense or evaporator, I forget) and said even when the fridge is turned off the fan will run until these fins are cooled to whatever point the thermister is..I would imagine what 100 degrees...?  He did not remember exactly what value that thermistor is.

There are both an upper and lower vented access on the exterior, so ventilation is pretty good. 

Still need an exhaust fan to keep it cooler? 

Will that actually help the fridge run more efficiently?

I?m confused!

I recently had to install a new Amish Built Cooling Unit in my Norcold 1201 refrigerator. I also installed three fans on the backside of the refer to aid in the venting of the hot air created by the refrigerator cooling unit. My fans are turned on at 130 degrees and off at 115 degrees by a thermal fan switch or (snap disc). The fans really do help in the cooling efficiency of your refrigerator especially if the refer is located in a slide out. Here's a video of my installation showing the fans I used and where the snap disc is located. http://www.youtube.com/watch?v=ZgjDl5nwPMo

1Sammiedog

 

[For Wheelin]

nice detailed slide show there 1Sammiedog...

Thanks,

 

[Gary RV_Wizard]

Note that a Norcold 12xx has two thermostatic cooling fans as standard equipment.  They are mounted near the top of the cooling unit.  Adding one or two more in the bottom can only help, though.

 

[For Wheelin]

I never really noticed how loud these fans are on other motorhomes...now I am learning that multiple fans for this purpose is rather typical.

I just picked up a quiet PC fan today that moves 50 cfm of air and runs at 16 dB...That gets installed this weekend.  If it is quiet enough but still needs more air flow, I put in another one.

 

[1Sammiedog]

I never really noticed how loud these fans are on other motorhomes...now I am learning that multiple fans for this purpose is rather typical.

I just picked up a quiet PC fan today that moves 50 cfm of air and runs at 16 dB...That gets installed this weekend.  If it is quiet enough but still needs more air flow, I put in another one.

Steve, These fans come in various sizes and CFM/RPM ranges. Depending on the RPM range will most likely determine how loud it is when running. Here are the fans I used. http://search.digikey.com/us/en/products/MEC0381V3-000U-A99/259-1490-ND/2021118

They were as close as I could find to the fans that came stock with my Norcold 1200. These fans are pretty quiet when running. I've been told that the best fans have ball bearings.

1Sammiedog