Condenser Cooling Fans

[wdk450]

Gang:
I was looking at the "Improve Your Cooling Performance Items" area in the rvcoolingunit.com website for a new inside refrigerator (evaporator) circulation fan, as mine is getting old and slower. Lubing it hasn't helped it that much, and I think the new units have bigger fans. Anyways, while in that section I saw some new (to me) different style fans particularly for removing the hot air from the top rear of the refrigerator compartment above the square-finned condenser. I ordered the deluxe kit with 2 fans, thermostat, switch and fuse. I am hoping to be able to mount the fans horizontally to the top inside of the top refrigerator vent cover with the airflow blowing to the outside. I plan to add a 2 wire connector assembly to be able to remove the vent cover.

The description of these fan kits says that they are particularly suited to refrigerators mounted in a slide. Here are links to the 3 kits they sell:

This first one is the cheapest, just the fan (1) only: http://rvcoolingunit.com/-Condenser-Fan-flush-mounted-wmounting-hardware-P5652854.aspx

The next one is 1 fan with the thermostat, switch, and fuse: http://rvcoolingunit.com/Condenser-Fan-1-Kit-wthermostat-and-wiring-Harness-P5652851.aspx

The last one is the one I ordered, 2 fans, switch, thermostat and fuse: http://rvcoolingunit.com/2-Condenser-Fan-Kits-wthermostat-and-wiring-Harness-P5672482.aspx

 

[BobTheBuilder]

I just purchased similar fans from another source and am going to do the same thing. However, in my 2011 Bighorn there is not enough space at the top to mount them as recommended (to the back of the vent opening, not enough clearance). I already have a partial baffle made from stiff sheet metal that extends part the way up from below the top vent opening. I am bending it in toward the fridge (just below the finned section), mounting the fans to the inside side of the sheet metal and putting them on rubber grommets. I will add a removable additional section of sheet metal to extend the baffle up to the fins.

 

[Gary521]

I just did a fix to my unit and it works. I added two large computer fans to the top vent with cable ties. To turn the fans on and off, I added a thermostat and attached it to the tubing that feeds the top condenser. I also modified the top of cabinet so the air does not get trapped above the refrigerator. Heartland adds a baffle to the newer units to direct air across the condenser but they have an inferior design of directing air away from the top on the unit. ( this is for refrigerators that are in slides )

I committed a no-no but adding screens to the side fridge vents to keep the bees out. Norcold told me to not add the screens as this inhibits air flow. The added fans fixed the flow issue with the screens on. Just for good measure, I am going to add a fan to the lower vent blowing in. For those of you that like lights on the outside of the trailer, the fans have blue leds that are on when the fans are running which gives a spooky look at night.

 

[WillyBill]

I just did a fix to my unit and it works. I added two large computer fans to the top vent with cable ties. To turn the fans on and off, I added a thermostat and attached it to the tubing that feeds the top condenser. I also modified the top of cabinet so the air does not get trapped above the refrigerator. Heartland adds a baffle to the newer units to direct air across the condenser but they have an inferior design of directing air away from the top on the unit. ( this is for refrigerators that are in slides )

I committed a no-no but adding screens to the side fridge vents to keep the bees out. Norcold told me to not add the screens as this inhibits air flow. The added fans fixed the flow issue with the screens on. Just for good measure, I am going to add a fan to the lower vent blowing in. For those of you that like lights on the outside of the trailer, the fans have blue leds that are on when the fans are running which gives a spooky look at night.

Hey Gary,

Besides getting "Spooked" tell us how well the mods worked.

Thanks,

WB

 

[Gary521]

I am not on any trip at the moment. So, to test the fan system, I turned on the fridge in 90 degree weather. After a few hours of running, the freezer was showing -3 at a arbitrary setting of 7. ( settings run 1-9 ) on a Norcold 18 cu ft Polarmax. Before, it was not getting below about 10 or so at a setting of 9 in those kind of temps. I did not want to take off the screens even though I sorta knew it was restricting air flow. I reviewed the Norcold install manual as saw how they wanted baffling installed. The manual shows an over the fridge baffle to direct air out of the enclosure. Heartland sorta directs air in this area but leaves a large opening for air to stagnate above the fridge. Holding my hand by the top vent, I can feel the heat flowing out with the new fans running. There are already three small fans behind the fridge, but in my case, these were not providing enough flow.
This was just a quick test as I just installed these things. I am going to add one more fan to the bottom vent to blow air in and up. I will retest when I get the fan in a couple of days. The thermostat I added is a Norcold 130 degree on stat. I used hose clamps to attach to the pipe. Norcold puts their stat on the condenser fins. The pipe flows into the fins. There is a stat the has a clip on it to attach to the pipe but this one was considerably more expensive.

These are the fans that I used: https://www.youtube.com/watch?v=0wVTP89-Btg

 

[esscobra]

so on my previous tt- I had installed the valterra fan near base of fridge behind vent panel- and used the thermostat until it stopped working and then just wired up to 12v switch- and down here in south texas where its 100+ the fan blowing upward towards the roof made a noticeable difference in the cooling of the fridge/freezer- the more airflow across the fins/coils the better it works- had I not gotten new bighorn I def would have added more fans -

 

[travelin2]

So Gary521, you have a Norcold 2118 and added 2 more fans to the standard 3?
We have the 2118 and on a setting higher than 6 we freeze items on the top shelf of the fridge even during summer temperatures of 80-90*.
I'm not understanding the need for additional fans
FWIW- in 5 years we've not have any insects invade that space i.e.: no screening


Sent from my iPhone using Tapatalk

 

[Gary521]

Where we live, we have bees all over the place. Some bee like the smell or they like something about propane and will build nests. I have screens on the furnace exhaust and the water heater vents. I am not worried about bees getting into the trailer just building nests where you don't want them to. There are lots of stories about nests in water heaters and refrigerators causing them to not work- you have been fortunate. The screens that I have on the refrigerator are Camco screens designed to fit on the Norcold. I have a car trailer and the bees build nests in hitch area. I have been stung. The **** bees build nests in the BBQ on my deck. I have been stung. So the minor issue of adding fans is no big deal to me as long as it works and it appears to. The fans are pretty cheap too.

According to some study I read someplace, screens cut airflow about 50% over not screens. That's a lot. So if I want screens, I have to add fans.

 

[wdk450]

When Norcold says no screens, I wonder if they are thinking of regular window screen fine mesh? It seems to me that a coarser mesh could still stop bees and wasps while not restricting airflow much. I also think that all the additional fans sort of negates the screen airflow restrictions.

The vent covers seem to be designed to allow airflow while pretty much preventing water intrusion from rain, driving in rain or rig washing.

 

[JohnD]

Yup!

Out here in Colorado we've got bees, hornets and wasps all over the place.

Last summer I discovered a wasp nest inside the kingpin the size of an orange.

Almost got stung when I pulled the pigtail out to plug it into the truck.

The nest is still in there (couldn't get it out), but a good spritz with a can of Raid wasp & hornet killer took care of them.

I've been battling a couple of other wasp nests behind the vinyl siding on our house, too . . .

I kill 'em . . . they come back to the same spot a few days later.

 

[Gary521]

Bill, I do not want to steal the thread you started. I was just trying to make your point that the fans do help with the refrigerator if you have some issues. After this started, I did some internet snooping and did find a couple papers on screens and airflow. The larger mesh screens have larger diameter wire and blah blah, it was all getting a bit technical. The long and short of it was that yup, the screens do restrict flow. So, if your fridge is struggling, try the fans. If your fridge is working ok the way it is, nothing required.

On my last trailer, a Bighorn 3055, I put screens on the lower fridge vent that I made myself. This time bought pre made screens. They are a bit more costly but are easier to install.

These are the screens: https://www.youtube.com/watch?v=ruKp5e_hbo8

Here is another video about screens and bees. This video was made in Colorado: https://www.youtube.com/watch?v=MAld_1ibkZ8

 

[wdk450]

Bill, I do not want to steal the thread you started. I was just trying to make your point that the fans do help with the refrigerator if you have some issues. After this started, I did some internet snooping and did find a couple papers on screens and airflow. The larger mesh screens have larger diameter wire and blah blah, it was all getting a bit technical. The long and short of it was that yup, the screens do restrict flow. So, if your fridge is struggling, try the fans. If your fridge is working ok the way it is, nothing required.

On my last trailer, a Bighorn 3055, I put screens on the lower fridge vent that I made myself. This time bought pre made screens. They are a bit more costly but are easier to install.

These are the screens: https://www.youtube.com/watch?v=ruKp5e_hbo8

Here is another video about screens and bees. This video was made in Colorado: https://www.youtube.com/watch?v=MAld_1ibkZ8

Gary 521:
I am not prideful enough to be worried about "thread stealing" as long as we are helping out our fellow RVers. Thanks for contributing.