Adding a Cooling Fan to a Norcold 1200

[_Rusty_]

I've seen on this forum the suggestion of adding a small fan to help circulate air on the back of the refrigerators. These past few weeks my unit seemed to struggle more than in years past, so I decided to add a fan. My question to the hive is: where to get DC power for this? My solution is marked in red on the attached schematic and I wonder if it is a good place.

On the schematic there is a point labeled DC HEAT and GND. I measured power here and found it to be ON when AC or LP was selected at the control panel. When ref. is turned OFF there is 0 vdc, so I hope to not run the battery down or have to disable when not in use.

What do you guys (and gals) think?

 

[Gary RV_Wizard]

All Norcold 1200s have a pair of fans in the "chimney" (#11 on your diagram). However, they aren't always sufficient if the chimney area is cluttered with wires (or critter nests) or if the upper vent is in the sidewall rather than the roof.

Your choice of 12v is probably ok as long as the fan power draw isn't too high (it's where the other fans get power), but why not draw power direct from the 12v supply to the back of the fridge? Typically that supply wire is 18 or even 16 gauge and has plenty of amp capacity. And use a thermostat-controlled fan.

 

[Kirk]

Amazon has many choices, but I would use one like this, or similar. I would get power from the 12V supply terminal block found at the bottom of the refrigerator, which probably looks something like this.

 

[Gary RV_Wizard]

Since the Norcold 1200 already has two large fans on a thermostat, they rarely need more than a little extra assist to get air moving in & up from the bottom vent. For that reason, I would not use the set that Kirk suggests in this particular refrigerator model. I recommend a single blower-type fan that directs a stream of air upward toward the large twin fans near the condensor.

 

[oldwildman]

Since the Norcold 1200 already has two large fans on a thermostat, they rarely need more than a little extra assist to get air moving in & up from the bottom vent. For that reason, I would not use the set that Kirk suggests in this particular refrigerator model. I recommend a single blower-type fan that directs a stream of air upward toward the large twin fans near the condensor.

Yep, two of those came with my RV. When I rebuilt the cooling unit, I moved them to a better position. They blow air right up through the large coiled piping into the upper area. They really help on the really hot days. Usually don't turn them on until the temps get into the mid 80's.

 

[_Rusty_]

This 12 v 250 mA computer fan is what I mounted. I save junk from basically anything I come across so this was a cheap start. Now i'm searching for a thermostat controller.

This one looks like it should work.

Yep, two of those came with my RV. When I rebuilt the cooling unit, I moved them to a better position. They blow air right up through the large coiled piping into the upper area. They really help on the really hot days. Usually don't turn them on until the temps get into the mid 80's.

 

[RayIN]

Since the Norcold 1200 already has two large fans on a thermostat, they rarely need more than a little extra assist to get air moving in & up from the bottom vent. For that reason, I would not use the set that Kirk suggests in this particular refrigerator model. I recommend a single blower-type fan that directs a stream of air upward toward the large twin fans near the condensor.

That's the setup I have. The blower type fan came with the ARP/FridgeDefend unit that keeps the absorption refrigerator from burning up. I picked up power from the main DC wire and zip-tied the fan to the bottom tubing of the cooling unit, pointed upwards towards the cooling tubes at the top.
After that installation I had to reduce internal temperature by 2 number settings to keep things from freezing.

 

[8Muddypaws]

Those types of digital temperature controllers are not known for being reliable. After reading the Amazon reviews I decided to use a simple button thermostatic switch. It served me well for several years, and then my Norcold 1201 sprung a leak. The irony is that the JC Refrigeration dual compressor cooling unit I installed when that happened has two such digital controllers.

I found replacements/spares on eBay for less than $10.

This is an old thread about ‘The Muddypaws Mod’. It might help.

The Muddypaws Mod for Norcold 1200 Refrigerators

After months of experimenting and helping the engineer develop an adjustable thermostat for Norcold refrigerators I discovered that mine was just not going to work with the thermostat anywhere but on the fin. For some reason it completely shuts down whenever it went into defrost mode. ...

www.rvforum.net

 

[_Rusty_]

Can anyone suggest a thermoswitch to control my fan? I purchased a thermo-swtch from Amazon but it did not work. As it turned out the switch was to "close" at 100°f but did not. I heated it with a heat gun and observed the temp with a Flir camera attached to my phone. Even after passing 160°f the switch did not close.

 

[Gary RV_Wizard]

Sounds like you received a defective thermal switch. Sometimes Amazon has knock-offs or just plain cheap crap. You didn't give the brand/model you bought, but I suggest you try another brand of switch or another source. If you Google Norcold 12v thermal fan switch, you get a lot of hits from different suppliers. JC Refrigeration might be a reliable source.