Norcold aux fan idea

[HD4Mark]

I put this together quickly to help our 1200 actually keep food cold. At a CG so my resources were limited so it didn't come out as clean of an installation as I might have done parked next to our garage but it works. The fans are simply attached with tie raps to the vent door and wired from the 12v behind the fridge through a toggle switch inside and an inline fuse. The fans came from Amazon.com: Cooler Master 120mm Silent Case Fan 4-in-1 Value Pack - (R4-S2S-124K-GP): Electronics

[Gary RVRoamer]

Your Norcold 1200 already has two fans mounted high in the cooling unit tower. Extra fans won't hurt, though, and may help on really hot days.

[paz]

I can't see from the ad if they're 12V or 120V, but that's a good price either way.

If you add 12V fans, just be sure they are wired correctly to blow in, not out or you'll upset the natural upward draft over the coils. If they're 120V, they will only blow one way, so you can't wire them incorrectly; but they still have to be mounted correctly.

Also, make sure the fan doesn't blow onto the burner so it doesn't disturb the flame

[bluepill]

Nice idea. Under what conditions do you switch them on?

Just a thought - If you want high and low speeds you can probably wire a series/parallel switch.

[bdaball]

I tried a similar arrangement with my Dometic but the refer temp imediately went up rather than down!

Why?

[HD4Mark]

Quote:

Originally Posted by Gary RVRoamer Your Norcold 1200 already has two fans mounted high in the cooling unit tower. Extra fans won't hurt, though, and may help on really hot days.

The two original fans quit. That is how I got started on the project. Since the Amazon fans were a 4 pack I got to thinking what to do with the others rather than just save them for back ups.

They are 12V and yes blowing in. I leave them running most of the time while we are here in the Florida Keys. The sun beats down on that side of the MH half the day and it is in the lower 80's by afternoon.

BTW I looked up online the cost of OEM fans and they were $50 each at one place (I will leave nameless but you can use Google too). When I can buy 4 at under $20 that work fine they should include a tube of KY to make that a little less painful

[JC2]

Quote:

Originally Posted by HD4Mark I put this together quickly to help our 1200 actually keep food cold. At a CG so my resources were limited so it didn't come out as clean of an installation as I might have done parked next to our garage but it works. The fans are simply attached with tie raps to the vent door and wired from the 12v behind the fridge through a toggle switch inside and an inline fuse. The fans came from Amazon.com: Cooler Master 120mm Silent Case Fan 4-in-1 Value Pack - (R4-S2S-124K-GP): Electronics

Last year while at the IRV2 national rally, I had a mobile tech install (2) of these type fans horizonally and flush with the upper inside of the frame of the exterior fridge cover.

Although our fridge would usually work satisfactorily when temps were 90 or below, I wanted to add additional cooling as we were heading to Vegas and Zion National Park after the rally. Left the rally and went to Vegas for a couple of days; temp was 112 degrees,(but a dry heat) and the freezer was at -5 to -10 in the freezer and 34 in the box at a setting of 4 -5. Went to Zion were the temps were in the low 100's and our fridge temps stayed the same. We turn ours on when we get setup with a simple on/off rocker switch and off when we leave. Gotta love those fans.

[Uber_D]

Quote:

Originally Posted by HD4Mark The two original fans quit. That is how I got started on the project. Since the Amazon fans were a 4 pack I got to thinking what to do with the others rather than just save them for back ups. They are 12V and yes blowing in. I leave them running most of the time while we are here in the Florida Keys. The sun beats down on that side of the MH half the day and it is in the lower 80's by afternoon. BTW I looked up online the cost of OEM fans and they were $50 each at one place (I will leave nameless but you can use Google too). When I can buy 4 at under $20 that work fine they should include a tube of KY to make that a little less painful

That is pretty cool! Excuse the lame humor. So you used these fans for the top mounts AND as an auxiliary intake. Very clever. With both oem fans going out at the same time was there anything else you found that would have caused that? Or maybe one went out a while ago and you didn't notice? Just curious what besides sour milk to look out for.

[HD4Mark]

Quote:

Originally Posted by Uber_D That is pretty cool! Excuse the lame humor. So you used these fans for the top mounts AND as an auxiliary intake. Very clever. With both oem fans going out at the same time was there anything else you found that would have caused that? Or maybe one went out a while ago and you didn't notice? Just curious what besides sour milk to look out for.

You should be able to hear the fans running on a hot day. Honestly I can't say I ever did but they are pretty quiet so I may have just not noticed. It is possible one went, it still was OK on one but after the second one it started getting warm in the fridge. You may be able to see them by looking up from the outside vent panel. To replace ours I had to pull the fridge into the RV about a foot to reach them. Temporarily I had stuck a small 12V auto dashboard fan in the opening until my PC fans arrived.

The sad part is that we had the cooling unit replaced last fall and used our Good Sam ESP to pay all but the deductible. The fans were running so they were not replaced. Had I known I would have replaced them out of pocket to not go through the work.

[AFChap]

When we had our cooling unit replaced the tech hooked the 12v to the board up backwards. Several months later when I realized the fans were not working the "fix" was to swap the 12v wires where they hook up to the board. As mentioned above, 12v fans will not run if the polarity is reversed.

bdaball --- did you set your fans up to push/pull air IN through the acess hole and then UP the stack vent toward the roof vent? If not (air flow wrong direction) , that would be the reason.

[bdaball]

Quote:

Originally Posted by AFChap bdaball --- did you set your fans up to push/pull air IN through the acess hole and then UP the stack vent toward the roof vent? If not (air flow wrong direction) , that would be the reason.

Yes.
I tried mounting the fan in two different location. 1, just inside the side wall cover similar to the picture with the fan pulling air in, and 2, farther up the stack space pushing the warm air up the stack. In both cases the refer temp rose several degrees instantly. And no, the vent roof cover is not plugged. And yes, you can feel some hot air coming up the stack if you remove the roof cover.

For now the fan sets in the spare parts bin.

[HD4Mark]

Quote:

Originally Posted by AFChap When we had our cooling unit replaced the tech hooked the 12v to the board up backwards.

Not hard to do since the wiring harness has a red wire and of course another red wire. I put a twister tie on the red wire that the red fan wire connected to on both fans to keep track of the polarity.

[Dr4Film]

I installed auxiliary fans into the Norcold rooftop vent last summer while in Alaska. My two OEM cooling fans located on the rear tubes decided that they would not run without sounding like a trashing machine so I disconnected them and installed four box fans.

My take on air flow is that it is far better to pull air through creating the cooling draft versus pushing air through trying to push the hot air out.

This is the thread - post #6.

Norcold 1200 fan tweak


Dr4Film ----- Richard.