Content area
Full Text
refrigeration zone
The compressor's discharge temperature can tell the service technician what is going on inside a refrigeration or air conditioning system. The discharge is a reflection of the hottest part of a refrigeration system, and there are limits as to how hot a discharge temperature should be. This article will explore discharge temperatures and their limits.
The discharge temperature can be measured by placing an insulated thermistor or thermocouple on the discharge line about 3 to 4 in. from the compressor. (See Figure 1.) The discharge temperature is a measure of the superheated refrigerant's vapor temperature. Since the compressor's discharge temperature is a superheated vapor temperature measurement, a pressure/temperature relationship does not exist, and a pressure gauge cannot be used for its measurement. Pressure gauges can only be used for a pressure/temperature relationship when a saturation temperature (evaporating and/or condensing) is wanted.
Since the compressor's discharge temperature is a reflection of what is going on inside the compressor, it must be monitored very closely. The back of the compressor's discharge valve is...