All About Norcold Thermal Limit Switch

It has been reported over the years that Norcold claims that their boiler housing (insulation canister) thermal switch does the same thing as the Fridge Defend.

Thus, we decided to put the Norcold 2M0802 high temperature limit switch to the test to see if there was any truth, after all, the Fridge Defend is patented. Our patent protects us from others copying our technology. Seen in the video is the Norcold insulation canister (boiler housing) which physically separates and insulates the switch from the boiler. See the video, read the rest of this webpage, and you decide if there is any similarity between the Norcold part and the Fridge Defend.

Brown font - quotes from Norcold:
Default1 Fridge Defend Set-Point ~422°F (217°C) - Boiler Steel Strongest
Norcold Set-Point @ 48°F2 ~1525°F (829°C) - Boiler Steel Not Safe
Video Length: 1:14 (minutes:seconds)
Actual Test Length: 23:05
Sample Rate 1 second
"WARNING: The thermal switch is not intended to be reset more than once."3 Fridge Defend turns off fridge when overheat, and then automatically restarts fridge
"thermal switch mounted on the insulation canister"3 Fridge Defend sensor mounted on boiler tube immediately detecting excessive boiler temperature. Temperatures above ~422°F (217°C) damage the fridge which leads to failures and fires.

Results from Norcold Thermal Limit Switch in Graphical Format

Norcold  Thermal Fuse Set-Point

The plot/curve above is the results from the test seen in the video. The horizontal axis is read from sensor (D) seen in the picture below. The vertical axis is the senor (B) on the boiler tube which reflects the temperature that the Fridge Defend will use to control the fridge.

Test Setup

Norcold Thermal Switch Test

A) We opened a small gap in the electric heater access door to show the electric heater turning red hot.
B) A precision temperature sensor was attached to the boiler tube.
C) The boiler tube temperature sensor is data logged by the meter on the left.
D) A precision temperature sensor is placed between the boiler housing and the Norcold thermal switch.
E) The Norcold part number 2M0802 thermal limit switch4 set-point temperature is data logged by the meter on the right.
F) A blue LED simulates the refrigerator power through the thermal switch, when the blue LED turns off, the Norcold fridge turns off.

This test was conducted with a Norcold boiler that did not have any fluids nor pressure in it. We attempted to test the Norcold boiler housing thermal switch on a working fridge, but we reached temperatures that were unsafe to continue testing. Thus, we had to use a boiler that was not pressurized for our own safety.

NHTSA Recall Campaign 09E-026 & 09E-027

Norcold Models listed in tables below from years 1996-2002 add thermal switch kit on replacment cooling units. For fridge after the year 2005, the thermal switch is standard equipment.

Norcold N6xx Series RV Fridge

Model Affected Manufacture Date Serial Numbers
N6 Models or N6xx January 1, 2009 to December 31, 2013 11769547 to 18602204

Norcold N6 or N6xx Models That Have Boiler Failure Leading to Fire

N610 N640.3F N641SSF
N611 N641 N641WH
N611C N641.3 NX611
N611F N641.3F NX611F
N611V N641.3SS NX641
N611VF N641.3WH NX641.3
N615 N641BK NX641.3BK
N620 N641BKF NX641.3F
N621 N641F NX641.3SS
N621F N641IM NX641BK
N621SS N641IMF NX641SS
N623 N641IMSS NXA641
N624 N641IMSSF NXA641.3
N640.3 N641SS NXA641IM

Norcold N8xx Series RV Fridge

Model Affected Manufacture Date Serial Numbers
N8 or N8xx Models January 1, 2009 to December 31, 2013 11769681 to 18602266

Norcold N8 or N8xx Models That Have Boiler Failure Leading to Fire

N810 N841.3F N842IMSSF
N811 N841.3SS N842SS
N811C N841.3WH N842SSF
N811CF N841BK N843IM
N811F N841BKF N843IMF
N811V N841BKV N843IMSS
N811VF N841F N843IMSSF
N814F2 N841IM NX811
N820 N841IMBK NX811F
N821 N841IMBKF NX841
N821BK N841IMF NX841.3BKF
N821BKF N841IMSS NX841.3SS
N821H N841IMV NX841IMF
N822 N841SS NX841SS
N822F N841SSF NX841SSF
N823 N842 NXA841
N824 N842F NXA841.3
N841 N842IM NXA841F
N841.3 N842IMF NXA841IM

Norcold 1082 & N1095 Models That Have Boiler Failure Leading to Fire

1082 N1095C N1095IMV
N1095 N1095IM N1095SS
N1095BK N1095IMBK N1095V
N1095BKV N1095IMSS N1095WH


1) We use the term "default turns off at 422°F" simply because the Fridge Defend can be tuned for either a Dometic, Norcold, or Amish cooling unit fridge. This will change the temperature that the Fridge Defend turns off a particular fridge heat source.

2) The Fridge Defend is designed to prevent damage to your refrigerator. When installed and maintained properly, the Fridge Defend will prevent the boiler temperature from ever reaching the damaging high temperatures that would eventually trigger the Norcold boiler housing Limit Switch. We do not recommend the removal of the Norcold device.

3) Norcold N6xx, N8xx, & N1095 Service Manual, page 38.

4) The Norcold kit started its life as a recall for most refrigerators as a result of fire issues. It comes as standard equipment on year 2007 onwards Norcold refrigerators, but is still the same as the recall.