BEER Frig Thermostat Design

[barryp49]

Hello All,

I have a U-Line BC 35 beermeister that has a failing thermostat. I can't get the temperature higher that 36F - the dial setting is below 1 (out of 7). Recommended to keep the beer at 38F. If I go lower the compressor no longer runs. The problem is that the unit is obsolete and a replacement thermostat is no longer available.

I am thinking about designing my owm and am wondering about the typical dead band. I am imagining that +-2 degrees F around the setpoint would keep the compressor from short cycling. I'm an embedded hardware/firmware engineer with some controls background but no regrigeration. The unit is basic, about 5 cubic feet, no freezer, no fan, condensor coil in the back, evap loop attached to "L" shaped aluminum plate in upper back inside of box.

1. Can someone tell me how much dead band I need?

2. Are there any other considerations?

Thank you,

Barry

[taz24]

Hello All,

I have a U-Line BC 35 beermeister that has a failing thermostat. I can't get the temperature higher that 36F - the dial setting is below 1 (out of 7). Recommended to keep the beer at 38F. If I go lower the compressor no longer runs. The problem is that the unit is obsolete and a replacement thermostat is no longer available.

I am thinking about designing my owm and am wondering about the typical dead band. I am imagining that +-2 degrees F around the setpoint would keep the compressor from short cycling. I'm an embedded hardware/firmware engineer with some controls background but no regrigeration. The unit is basic, about 5 cubic feet, no freezer, no fan, condensor coil in the back, evap loop attached to "L" shaped aluminum plate in upper back inside of box.

1. Can someone tell me how much dead band I need?

2. Are there any other considerations?

Thank you,

Barry


Hello Barry.

Thermostats are thermostats and are not specific to individual applications.
One thermostat is as good as another as long as it is in the same range.
The dead band could be as high as 5 degC but is not that important as long
as the liquid is not alowed to freeze.

Any stat that controls around the +8 degC (40 degF) range will do what you need,
they all have about a 5 or 6 deg range (a bit more in F).

If you are thinking about fitting an electronic controler then any controler will do
and you can set it to the temp range you want.

All the best taz.

.