Community Forums

crah · 01-06-2013, 03:35 PM

I'd like to do the Norcold 1200 muffin fan mod at the roof vent. Anyone have a source for the fans? It looks like the 4 fan set up would be optimal but I couldn't get the links to work in from the threads I found in the search.

Thanks

RV Wizard · 01-07-2013, 03:14 AM

Radio Shack is one of many sources for 12 dc computer fans.

paz · 01-07-2013, 05:42 AM

Google muffin fans. Check Amazon and eBay. Pay the extra maney and get fans with ball bearings. They will last longer than the ones with sleeve bearings. Since you will likely be removing the fridge to mount the fans, you don't want to be doing that every couple of years if one of the sleeve bearings starts to squeal.

For the Norcolds that came with fans, there are 2 mounted on top of the main coils. They are turned on when a sensor mounted to a fin on the very top coil reaches a pre-set temperature.

FreeByrd · 01-08-2013, 10:48 AM

Hey Crah,
You might want to look at "Future Electronics" and "Digi-Key". I have purchased fans from them in the past and they have a wide variety, including ball bearing and a newer "Mag-Lev" design fan from Sunon with much lower amperage draw.

Be sure to look at amperage, CFM (Air Movement in Cubic Feet/Minute) and Db (noise) for each to match what you're looking for.
Here's the Digi-Key website for DC Fans, you can filter out what you don't
want with the menu at the top. Prices in the right column are reasonable.

Fans, Thermal Management | Fans - DC | DigiKey

See Ya Out There,
Mike

crah · 02-04-2013, 11:17 PM

Hi mike

I bought 4 maglev 75 cfm Sunon fans from your digikey link. Thank you for the link. I have them mounted at the roof vent but haven't wired it up yet. Any suggestions? I think I see the original thermo disk/sensor on the condenser fin from the roof. Can I just splice those wires and tap into them and if so, can I make the wire connections with a small wire nut? I'm thinking if that is possible, I would run an extra hot wire directly and tie that to a switch inside the coach. Any tips or tricks would be appreciated.

Mr_D · 02-04-2013, 11:41 PM

I ordered a surplus gang of four fans in an aluminum bracket last year from "All Electronics". Haven't mounted them yet so need to get busy and do it.
Cost was less than $15 but the last catalog I got from them didn't have them any more.

336muffin · 02-05-2013, 01:18 AM

I found mine at Radio Shack for $9.95, my roof hole used five perfectly. I didn't want to fill in the difference if I only used two or three it might restrict air flow when not turned on. I installed a manual switch to control them when I seen fit. I have not regretted doing so. I can access mine from the roof if I take the cover off.

Gorlininc · 02-05-2013, 03:16 AM

Hi
I have a Norcold 1210 refrig . I know about their recalls. I'm fairly new at all this. Why are fans being placed in the roof vent of the Norcold. I never heard of that before.
Btw. I put a temperature gauge in my fridge and freezer today. Frige is 34 degrees and freezer is 9 degrees. Not too bad. Ice cream is frozen. I had some today.

336muffin · 02-05-2013, 07:23 AM

My Norcold averages -3 in the freezer and 36 in fridge on setting #3 with the fans off. We have done the Amish cooling unit.

Sky_Boss · 02-05-2013, 07:49 AM

[QUOTE=Gorlininc;1453564]Hi
I have a Norcold 1210 refrig . I know about their recalls. I'm fairly new at all this. Why are fans being placed in the roof vent of the Norcold. I never heard of that before. .../QUOTE]

The purpose is to help air movement over the cooling unit. The more air the moves over them, the more heat is dissipated helping the cooling unit to work better.

When the refer is NOT in a slide out then it vents straight up through the roof vent. Sometimes the construction creates some "dead space" above the refer (my Winnebago had one) that seems to disrupt the flow. The theory behind the fan up close to the roof vent is to "force" more air flow. When I had the Amish Cooling Unit installed, I had them add a fan. It all seemed to help.

RVs with the refer in the slide out have baffle to vent out the side of the slide out. Again, there is some thought that adding a fan or 2 helps increase the airflow over the cooling unit coils.

BTW, if I had to do it again, I would have put in a separate switch to control the extra fan. During cool weather it wasn't needed.

FreeByrd · 02-05-2013, 09:27 AM

Hi Crah,
I found it easier to access the 12 volt feed to the fridge. This is the 10 ga. wire supply for the circuit board in the back of the unit. I used a 3 way splice and power the fans with 2 Single Pole, Single Throw (automotive) switches. One runs one of 3, the other runs the other 2 and allows me to pick how much air movement I want given the outside temp.
If it's easier to pick up the "Hot" side of the fan Thermostat, that would also work given the low amperage draw. I'd still install a low amperage fuse to be safe.
My switches are in my lower fridge vent, you might want to think about installing them inside the rig near the fridge if you have access. . . . just easier to work with.
Mike

Ed-Sommers · 02-05-2013, 10:00 AM

My thoughts are for the fans to be pushing air onto the coils so the hot air rises throuth the normal configuration.

Muffin fans are not able to suck air in even a fraction of the efficiency of the pushing of air, by design.

Also, two muffin fans with and on/off switch installed at the coils are easily accessible as needed.

Ed

Dr4Film · 02-05-2013, 10:45 AM

This how I did it back in the summer of 2010 when we were staying in Fairbanks Alaska.

Post #12.

http://www.irv2.com/forums/f54/addin...dge-86697.html

The fans I chose were from Amazon and they had the new Sony S-FDB bearing technology.

Scythe S-FLEX™ S-FDB 120mm FAN

Those 75 CFM ones are no longer available but the SFF 63 CFM ones are from Amazon.

Amazon.com: Scythe S-FLEX SFF21D / 120mm 800rpm Fan.: Computers & Accessories

I have recently sold the package to another iRV2.com member. I installed a Samsung residential back in April 2012.
Dr4Film ----- Richard

crah · 02-05-2013, 11:28 AM

Thank you for all the info.

To some of the posters asking why the fans, I need them due to the poor performance my my Norcold due to two conditions. The Norcold works fine if the weather is below 88 or so. Above that and it struggles to get below 43 degrees. Also when I drive, I discovered the wind turbulance traps the hot air and my temp climbs almost up to 50 if it is above 90 out. The fans will create a constant exhaust which aids the cooling process for these absorption refrigerators.

My factory set up came with two fans that are mounted midway that blow up but is useless as the turbulance just traps the hot air.

My set up with the 4 fans almost takes up the entire roof vent opening which will work great for exhausting the air.

On a final note, I never realized my fridge temperature rose when driving until last summer. I put a remote temp sensor and the display at the drivers seat. That's when I discovered it.

I guess I lived through the previous years not knowing my food was getting warm.