Unit Startup

Unit Start-Up Procedures

Daily Unit Start-Up

1.Verify the chilled water pump and condenser water pump starter are in “ON” or “AUTO”.

2.Verify the cooling tower is in “ON” or “AUTO”.

3.Check both oil tank oil level(s); the level must be visible in or above the lower sight glass. Also, be sure to check the oil tank temperature; normal oil tank temperature before start-up is 140°F to 145°F (60 to 63°C).

4.Note: Each oil heater is energized during the compressor off cycle. During unit operation, the oil tank heater is de-energized.

5.Check the chilled water setpoint and readjust it, if necessary, in the Chiller Settings menu.

6.If necessary, readjust the current limit setpoint in the Chiller Setpoints menu.

7.Press “AUTO”.

The UCP also checks compressor motor winding temperature, and a minimum restart time is initiated if the winding temperature is less than 265°F. The chilled water pump relay is energized and evaporator water flow is proven.

Next, the UCP checks the leaving evaporator water temperature and compares it to the chilled water setpoint. If the difference between these values is less than the start differential setpoint, cooling is not needed.

If the UCP determines that the difference between the evaporator leaving water temperature and chilled water setpoint exceeds the start differential setpoint, the unit enters the initiate Start Mode and the oil pump and Refrigerant pump and the condenser water pump are started. If condenser water flow is not proven (flow switch 5S3 does not close) within 4-minutes 15 seconds, the unit is locked out on a MMR Diagnostic.

Oil pressure must be verified within 3 minutes or a MMR diagnostic is generated.

When less than 5 seconds remain on the restart inhibit, the pre-start starter test is conducted on Y-Delta starters. If faults are detected, the unit’s compressor will not start, and a MMR Diagnostic will be generated.

If the compressor motor starts and accelerates successfully, “Unit is Running” appears on the display. At this time the purge unit will start operating on “Automatic” and will continue to operate as long as chiller compressor is running.

Note: Whenever the UCP detects a MMR diagnostic condition during start-up, unit operation is locked out, and manual reset is required before the start-up sequence can begin again. If the fault condition has not cleared, the UCP will not permit restart.

CDHF-SVU01C-EN

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American Standard CH530 manual Unit Startup, Unit Start-Up Procedures, Daily Unit Start-Up