What is the typical PaceController cycle?

After the initial “off” period, a typical PaceController compressor cycle is:

ON Cycle

Before being activated by the PaceController, gas is collecting on the suction side of the compressor. When the PaceController is activated, the compressor initiates its pumping process with an increasing density of refrigerant gas and encapsulated oil mist.
At the beginning of the cycle, the thermal expansion valve (TXV) is at its maximum opening. This maximum flow of dense gas fills each stroke of the compressor, providing the highest volumetric efficiency and also cooling of the compressor electrical windings.
As the compressor continues in the “ON” cycle, the TXV begins to restrict the volume of refrigerant entering the evaporator, due to the cooling effect sensed by the TXV temperature sensor, causing a reduction in the supply of refrigerant to the suction side of the compressor.

OFF Cycle

After the preset “ON” cycle, the PaceController de-energizes the compressor control circuit for a few minutes. However, cooling and dehumidification continue as the fan moves air over the coils below the dew point. The following also occur:

  • Condenser: condensation of hot gas to liquid continues
  • Evaporator: air moves across the coil; dehumidifying and cooling continue
  • System: all pressures balance
  • Energy: none is consumed by the compressor until the PaceController again allows the compressor control circuit to be energized.


At a preset interval, the PaceController again allows the compressor control circuit to energize and repeat this optimum cycle.