C h i l l e r O p e r a t i o n S e q u e n c e

The EarthSmart ECM Series Chiller has a unique user interface that controls the process temperature and prevents refrigeration migration during compressor off times.

When the main power is connected:

1Depending on the state of the refrigeration system, the compressor may turn on momentarily upon connecting power. The compressor will stop when the refrigerant is pumped into the condenser and a low pressure condition exists in the evaporator.

When the power toggle switch is turned to the “On”or “I” position:

2Turning the toggle switch on immediately starts the process pump and illuminates the control. When flow is established and the unit is not in a low temperature alarm, the Liquid Line Solenoid valve (LLSV) will open. This allows the refrigerant to migrate to the evaporator and increase the pressure. When the low refrigerant pressure switch is satisfied the compressor will turn on and process coolant will begin cooling.

3When the process temperature is above setpoint the compressor will run and the Hot-Gas Bypass valve (HGBP) will not open. If the process temperature falls below the setpoint, the HGBP valve will energize, raising the actual process temperature to maintain the user-entered setpoint temperature. The HGBP valve can energize up to 9 out of 10 seconds. If there is less load on the chiller and the temperature continues to fall to 4°F {2.2°C} below the user-entered setpoint the controller will alarm (A2.lo) and close the LLSV. The compressor will pump the refrigerant out of the evaporator and the low pressure switch will shut off the compressor. This is a normal function of the chiller and will not require troubleshooting.

4The controller stays in this alarm condition (A2.lo) until the temperature is 2°F {1.1°C} above the user-entered setpoint, at which point the controller allows the LLSV to re-open and the compressor to restart.

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