norcold. timer or thermostat?

[motion30]

I have a norcold refrigerator, and.its.working fine. ,we recently had a cold front come tru and lower the temperature from the high 70's to the high 50's . when I happened to look at the thermometer I had installed in the fridge the temp dropped from usual 40 down to 33 degrees. I have noticed in the past the starting and stopping off the compressor has little to do with the actual box temperature. So my question is does this thing actually have thermostat or is it simply a timer that controls the temperature

[Cheechako]

I dont know but mine seems to never turn off. Replaced both t-stat and adjustment module to no avail, Norcold are notorious for these problems.

[Richard Kollmann]

Small home refrigerators and all well designed 12/24 volt boat ice box conversion units with Danfoss BD or Norcold Swing compressors use a thermostat that controls evaporator temperatures. Compressor run timers are sometimes used on large holding plate systems but not on standard refrigeration. There are three good reasons for controlling evaporator temperature instead of box temperature:

• Box temperature is more stable from 1 to 3 degrees as compressor cycles based on evaporator temperatures.
• Evaporator temperatures are always15 to 20 degrees colder than box temperature providing an area in box to store or freeze a few items like ice.
• The Most important reason to stay with evaporator controlled thermostats is they are more energy efficient than area thermostats or timers. Snap action or electronic thermostats controlling a zone or area will tend to overpower the evaporators ability to absorb heat efficiently increasing daily amp-hrs consumed.

The main problem with only controlling evaporator temperatures in stead of box temperature in mobile units like boat refrigeration is the wide swing in climate conditions and amount of box insulation. The only solution to this problem is resetting thermostat control with large ambient temperature changes.

[motion30]

Thanks Richard. that explains exactly how my refrigerator is acting. No problem I was just curious