Norcold 641 Moisture Reduction Heater Question

Question

Just got a used 641 installed and going. Have a question about this heater mentioned in the manual. That says it is in the centre divider between the doors and operates only when the fridge is ON and DC power is sufficient.

I remember posts on here about ISTR Dometic fridges that have a switch in the door that you can turn this feature off, but that might not be the same thing?

Also, there is an optional "Low Ambient Heater" with 3 amp fuse you can pull, but looking at Google for this, I don't seem to have one.

Questions are:
1. Can the moisture reduction heater be turned off, and how?
2. How many DC amps does it draw when on?

I ran the fridge to see the amps on the Trimetric, and got:

A. LP--burner lit- 00.7 amps
B. AC-- 00.5 amps
C. LP--door open, light on--1.1 amps

I don't know if it would be worth turning that heater off when off-grid. If answers to above come in, then I will know.

Thanks

old-biscuit · Answer

NO..there is NO On/Off Switch for the Moisture Reduction Heater'
It is ON when Fridge is ON
.11 to .17 amp draw

Automatic Ignition .50A
Interior Light .60A
Gas Valve .14A

3A thermal switch would be for Ice Maker/////water line heater

bfl13 · Answer

Thanks!  So not enough to worry about.BTW, the thermal switch in this case seems to be part of a "Low Ambient Heater kit, that goes in the back cooling "chimney" somehow in the Goolge info. (I will edit the OP for that, sorry) It is a resistance heater.  Has +12v black wire through a 3a fuse, and a -12v BR wire though a thermal switch.  The manual just says it is for cold weather to help with heating.  It might also be whatever an ARP is, I am not clear on all that.   I don't have one AFAIK.641.3R  What does the R stand for?  Can't find a list of options that might refer to.

old-biscuit · Answer

Low Ambient Heater is for 'cold/freezing' camping
It is a heated wire that is thread up/attached to cooling coils to keep the 'coolant' warm so fridge will operate in sub 32*F temps

The .3 in your model (N641.3R) indicates a DC Heater (30A)

The 'R'-----haven't a clue

pianotuna · Answer

Hi BFL13,From the cold weather camping thread. "Norcold now make (and install on all new Norcold refrigerators), a "Cold Weather Kit" (Norcold part number 634913) that will allow the refrigerator to safely operate down to zero degrees (f I guess).https://forums.goodsamclub.com/index.cfm/fuseaction/thread/tid/24160748/srt/pa/pging/1/page/11.cfm

pnichols · Answer

Old-Biscuit wrote:Low Ambient Heater is for 'cold/freezing' campingIt is a heated wire that is thread up/attached to cooling coils to keep the 'coolant' warm so fridge will operate in sub 32*F tempsThe .3 in your model (N641.3R) indicates a DC Heater (30A)The 'R'-----haven't a clueWell ... how often are the interiors of RVs at those low temperatures such that their absorption refrigerators are also exposed to those kind of low interior temperatures surrounding them?I have a good old Norcold 611 in our Class C and it even helps to keep the cabinet around itself warm from to it's system electric or propane heaters whenever it is cycling/operating.I can see an absorption refrigerator having problems operating in cold temperatures in, say, a shed out in the backyard in winter ... but inside an RV that is normally kept warm enough for us humans?

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Norcold 641 Moisture Reduction Heater Question

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