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Low temp conditions

I have a 3 ton cooling only unit that will only work down to 0 degrees F. I know this is the factory limit but the problem is the unit cools a server room. I need to make this unit run at a colder temp. I was thinking of interupting the outdoor air thermister with a 75 k ohm resistor. Will this work?

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Re: Low temp conditions

75k ohms resistor is lower than 0 degrees F in equivalent temperature may be compressor cannot operate because the maximum setting of thermostat. is from 17 to 18deg. C. You can use 11 to 12k ohms the temp. for this is about 23 to 24 deg. C. The resistor resistance is fixed so the compressor continue running without cut out. The only problem for this is the compressor, because the design of the compressor is for high temp. Continue running of compressor can produce icing in suction and evaporator coil and cause damage of compressor due to liquid slugging.

Posted on Jan 17, 2008

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