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Articles by John Tomczyk
Often, compressors in the refrigeration and air conditioning fields have forced oiling systems. Here is a look at some of those oil pumps.
An overview of the oil check valve, which will only let oil pass from the compressor’s motor barrel to its crankcase.
The compressor’s discharge line temperature is important because it is an indication of the amount of heat absorbed in the evaporator and suction line and any heat of compression generated by the compression process.
Migration of refrigerant to the compressor’s crankcase during an off cycle is a serious problem, as significant compressor damage can occur if the problem is not remedied.
This column will try to explain the voltages associated with the high or wild leg coming from the secondary of a Delta service transformer.
John Tomczyk discusses the Wye or Star configuration of the three-phase electrical service, which usually delivers four wires to the building.
When refrigeration systems are exposed to low-ambient conditions, the condensing pressure (head pressure) will fall. If the head pressure gets too low, the metering device will not have enough pressure drop across it to operate properly.
The thermostatic expansion valve (TXV or TEV) is a metering device located between the liquid line and the evaporator.
John Tomczyk, Professor of HVACR at Ferris State University and co-author of Refrigeration and Air Conditioning Technology, discusses refrigerant undercharge.