Thermostat control / compressor life

[0202]

This seems like it should have been (and likely has elusively been) addressed, but I can't seem to pull up a definitive post.

I'm taking the dive and converting a Frigidaire FRC445GM this weekend and had a few basic questions on using a thermostat control. From conversions here, it seems that leaving the fridge on setting 1 of 7 will get the beer to near 40f - but I feel more comfortable installing a digital thermometer to keep the temperature specific.

If I set a "swing" range of 4 degrees f or so, is controlling the compressor with a thermostat prone to shortening the lifespan of the kegerator? It seems like it would be just as much work as leaving it on setting 1 for the compressor, but I'm no refrigeration engineer.

Thanks in advance!

 

[mosquitocontrol]

I have the same model and would like to offer some comments. I have two kegs in mine at any one time, in varying degrees of fullness. The thermostat of the fridge will be based off temperature settings of the air in the fridge. The temperature of the air can swing some amount of degrees before the compressor kicks on to return to temp. The beer in the kegs has much more thermal mass then the air, and will stay at relatively constant tempreatures, at least in comparison to the surrounding air. With this in mind, although the fridge thermostat can swing probably +/-4 degrees, the actually temperature of the beer will not. I don't think an external thermostat controller will do you much good in this situation. I've had a thermometer measuring the temperature of my keg (taped to the keg) and its been measuring a constant 38 degrees (within .5degrees or so) for the last 24 hours without the door opening.

Think of it this way, if you open the door of the fridge, the air in the fridge will go down to 50/60F. In the time it cools back down, your beer temperature will have a negligible change of a degree or two (if at all) and that is the most extreme you would get.

So really the only time you need a external temperature controller is if you desire a temperature outside the range of the appliance. Mainly, using a freezer to maintain fridge temperatures or a mini fridge to maintain fermentation temperatures. Or if the temperature control of the device has been proven to be highly inconsistent. But in that case I'd probably recommend a newer appliance.

 

[0202]

So the fridge thermostat is reliable enough to not freeze my kegs, and to keep the temp relatively stable?

I was also interested in dual purposing the fridge for fermenting, but I should probably build a dedicated fermentation box.

 

[mosquitocontrol]

I've been watching the temperature of my keg all day ( can see it from the computer). The lowest I've seen is 37.8 and the high of 40.0f. Just trying to give you info so you don't have to spend money on stuff that is t necessary. I have thru door taps and haven't opened the door all day.

 

[remilard]

With temp controllers I think the trick to not killing the compressor is to not measure the temperature of the air. The temp of the beer or some proxy substance is much more table than air and even with a 1 degree differential the compressor does not cycle on and off very often.

 

[0202]

Thanks for the input.

I think I'm going to leave the fridge as it is and keep it as a kegerator dedicated serving vessel. I'm still going to order the controller, but I'll just build a fermentation chiller and use it there.

Can't wait for my stuff to get here