compressor is running in a lightly loaded condition. This cycling of the chiller is normal and is

known as recycle. A recycle shutdown is initiated when any of the following conditions are true:

when in LCW control, the LEAVING CHILLED WATER temperature is more than 5° F (3° C) below the control point, and the CONTROL POINT has not increased in the last 5 minutes

when ECW CONTROL OPTION is enabled, the ENTERING CHILLED WATER tem- perature is more than 5° F (3° C) below the CONTROL POINT, and the CONTROL POINT has not increased in the last 5 minutes

when the LEAVING CHILLED WATER temperature is within 3° F (2° C) of the BRINE REFRIG TRIPPOINT.

When the machine is in RECYCLE mode, the chilled water pump relay remains energized so

that the chilled water temperature can be monitored for increasing load. The recycle control

uses RECYCLE RESTART DELTA T to check when the compressor should be restarted. This

is an operator-configured function which defaults to 5° F (3° C). This value is viewed/modified

on the Service1 table. The compressor will restart when:

in LCW CONTROL the LEAVING CHILLED WATER temperature is greater than the CONTROL POINT plus the RECYCLE RESTART DELTA T; or

in ECW CONTROL, the ENTERING CHILLED WATER temperature is greater than the CONTROL POINT plus the RECYCLE RESTART DELTA T

Once these conditions are met, the compressor shall initiate a start-up, with a normal start-up

sequence.

An alert condition may be generated if 5 or more RECYCLE STARTUPs occur in less than 4

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Carrier PC211 specifications