Norcold Fridge constantly running

S810

The Norcold 2-way fridge in my 2019 Tab 400 Boondock is set to zero but constantly runs.  I cannot get it to turn off completely so is this normal?  Any information or experience would be much appreciated. 

MuttonChops

Disclaimer:  No direct 2-Way Fridge experience.

A yr-2019 TAB 400 most likely has the Norcold NR-740 series Fridge.
nüCamp installed these to operate on 12VDC only, when on Shore Power the WFCO Power Center not the battery powers the Fridge { not valid for yr-2019, occurred during a later production year. }

NR-740 User Manual states when the Thermostat is set to " Off " the Fridge is off.
Assuming your reference to " Zero " means the Thermostat is at it's lowest setting (off)
then it seems your Thermostat has failed ( a common failure BTW )

Replacements are available for around $35 on the web.
Do confirm your Fridge Model Number before ordering.

Until a replacement is installed. . . .
Your trailer may have a 12VDC Power to Fridge toggle switch,
turning it off will stop the Fridge operation.
If not on most rigs the DC Fuse panel position #9 feeds the Fridge remove it to turn-off.
   Check to see if your Power Center has a list of DC Fuse Circuits to confirm Fuse # to remove.

drackus

I also have a 2019 Tab 400 with the Norcold fridge.  It was not running consistently.  I installed a new thermostat and it works perfectly now.  

I ordered the replacement from the RV Fridge Guys. https://rvfridgeguys.com/

Norcold Thermostat Control Assembly 635832 (NR740/ NR751)

635832

By the way, my 2 way fridge is wired into both the 12v system and the 120v system.  

MuttonChops

drackus said:
By the way, my 2 way fridge is wired into both the 12v system and the 120v system.  

The exact Month/Year nüCamp switched to only wiring the 12V side is unclear.
Most owner remarks suggest it may have occurred before year-2022 when it appeared in the updated Owners Manual.

I'll edit my earlier post in this thread.

S810

Well,  I bought and installed a new thermostat control and when I turned the power on the fridge was running in the off 'zero' position again.  

I turned the breaker off and it shut off for about 3 seconds then started running again with the breaker off!  

I had to remove the fuse and turn the breaker off to get it to stop running!!  Ugh....

Horigan

To pull power from the frig you need to flip the 120V breaker, if on shore power, and the 12V fuse. 

On my 2019 400 there is a distinctive “click” when it switches to OFF.  In the thermostat there is an internal rotary ramp that is engaged in the OFF position.  I recall my thermostat had an issue with getting over the ramp to OFF and I replaced it. 

drackus

When you disconnect your thermostat (ie remove at least one of the leads), does your fridge stop?

if so, it points to a bad thermostat.  If your fridge runs when the thermostat is disconnected, it could be a short in the wiring or a control board issue.