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Jeff Erbele
12-04-2013, 6:25 AM
I have a secondary fridge in the garage. The garage is insulated but unheated. We are having a cold snap and the garage temperature will drop, maybe even freezing. In past winters when it gets really cold, the refrigerator runs non-stop. That sort of does not make sense. It should not have to run because the air outside the fridge is about the same temperature or maybe lower than the temperature inside the fridge.

My question is why does it run more when the ambient temperature is near freezing or below freezing than when the ambient temp is hot, may in the 90's F or higher?

I know a lot about a lot of things, but HVAC is not my strong suite. I suspect the answer lies in the principles of refrigeration. My guess is the refrigerant is not converting from vapor to liquid or liquid to vapor, or not as much as it should.
There is either liquid where there should be vapor, or vapor where there should be liquid inside the system or in the refrigeration cycle. Is this the problem? If so which one? Is this called vapor locked?

My guess to "why?" is there is not enough of a temperature differential or the condenser is frozen.

As you can see, I know just enough to be dangerous :)

What could I do, or should do about the fridge running non-stop?
Just Turn it off for a while, or leave it off until the I need to augment the cooling inside the fridge?

Jim Matthews
12-04-2013, 7:17 AM
Three things to check, two are simple -

Is the door seal still tight? You can check with a dollar bill as a feeler gauge.
Is the freezer coil frozen? It may not exchange heat in the compartment, and sends a false reading.

The last is the thermostat - that's likely under some covers inside the refridgeration compartment.

My first guess would be the thermostat.

Jeff Erbele
12-04-2013, 10:41 PM
Three things to check, two are simple -

Is the door seal still tight? You can check with a dollar bill as a feeler gauge.
Is the freezer coil frozen? It may not exchange heat in the compartment, and sends a false reading.

The last is the thermostat - that's likely under some covers inside the refridgeration compartment.

My first guess would be the thermostat.

Perhaps my question was not to the point.

The fridge in the unheated garage and runs non-stop when the garage gets really cold. Why?
One would expect a fridge to run more when the garage is 90 degrees, but it run less then, only cycling on and off as needed.

To answer your questions the door seal and the thermostat are the same, year after year, season after season.
The fridge is a 16 cu ft Kenmore with the thermostat easily accessible in clear view like most residential models. It is all fridge, no freezer, by factor design.

Frozen Coil - No Idea. The outside, back of the fridge is smooth sheet metal. My guess is, it is under the fridge, on the back side.
Accessing that is a major project as the fridge is on pedestal, about 2 feet high, in the corner of the garage with shelving on the third side.
What would cause it to freeze?
How do I know if it is?
If it is, what should I do about it?

Mike Henderson
12-04-2013, 11:16 PM
The thermostat in the refrigerator should control whether the compressor turns on or not. Perhaps there's some problem that can occur if the compressor is subjected to freezing temperature and that over-rides the thermostat - the compressor runs to generate heat for itself. If so, it may have a bypass for the refrigerant so the inside is not cooled excessively.

But all this is a guess - I have no experience with refrigerators in such conditions.

Mike