RV.Net Open Roads Forum: Tech Issues: Norcold 641 Moisture Reduction Heater Question

RV Blog

  |  

RV Sales

  |  

Campgrounds

  |  

RV Parks

  |  

RV Club

  |  

RV Buyers Guide

  |  

Roadside Assistance

  |  

Extended Service Plan

  |  

RV Travel Assistance

  |  

RV Credit Card

  |  

RV Loans

Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tech Issues

Open Roads Forum  >  Tech Issues

 > Norcold 641 Moisture Reduction Heater Question

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Sponsored By:
BFL13

Victoria, BC

Senior Member

Joined: 02/15/2006

View Profile



Posted: 01/04/20 04:07pm Link  |  Quote  |  Print  |  Notify Moderator

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

* This post was last edited 01/04/20 05:16pm by BFL13 *   View edit history


1991 Oakland 28DB Class C
on Ford E350-460-7.5 Gas EFI
See Profile for House electronics set-up.

Old-Biscuit

Verde Valley

Senior Member

Joined: 06/20/2009

View Profile



Posted: 01/04/20 04:44pm Link  |  Quote  |  Print  |  Notify Moderator

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


Is it time for your medication or mine?


2007 DODGE 3500 QC SRW 5.9L CTD In-Bed 'quiet gen'
2007 HitchHiker II 32.5 UKTG 2000W Xantex Inverter
On the Road Debt Free April '07
Off the road still Debt Free Jan. '14

BFL13

Victoria, BC

Senior Member

Joined: 02/15/2006

View Profile



Posted: 01/04/20 05:15pm Link  |  Quote  |  Print  |  Notify Moderator

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

Verde Valley

Senior Member

Joined: 06/20/2009

View Profile



Posted: 01/04/20 06:16pm Link  |  Quote  |  Print  |  Notify Moderator

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

Regina, SK, Canada

Senior Member

Joined: 12/18/2004

View Profile


Offline
Posted: 01/05/20 02:48pm Link  |  Quote  |  Print  |  Notify Moderator

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


Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp hours of AGM in two battery banks 12 volt batteries, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.

pnichols

The Other California

Senior Member

Joined: 04/26/2005

View Profile



Good Sam RV Club Member


Posted: 01/09/20 10:54am Link  |  Quote  |  Print  |  Notify Moderator

Old-Biscuit wrote:

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


Well ... 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?


Phil, 2005 E450 Itasca Spirit 24V

BFL13

Victoria, BC

Senior Member

Joined: 02/15/2006

View Profile



Posted: 01/09/20 02:55pm Link  |  Quote  |  Print  |  Notify Moderator

Seems similar to the ARP as I mentioned earlier. Can't say if the heater is necessary in sub-freezing temps, or just helps. The heater stuff is on the back of the fridge that faces the cold outside, so I can see it could get cold alright.

pianotuna

Regina, SK, Canada

Senior Member

Joined: 12/18/2004

View Profile


Offline
Posted: 01/09/20 08:33pm Link  |  Quote  |  Print  |  Notify Moderator

Hi Phil,

I can say a heater is necessary.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 

Open Roads Forum  >  Tech Issues

 > Norcold 641 Moisture Reduction Heater Question
Search:   Advanced Search

Search only in Tech Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:




© 2020 CWI, Inc. © 2020 Good Sam Enterprises, LLC. All Rights Reserved.