Carrier 17/19EX User Manual
Page 123
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
hours. This excessive recycling can reduce machine life. Compressor recycling due to
extremely low loads should be reduced. To reduce compressor recycling, use the time schedule
to shut the machine down during low load operation or increase the machine load by running
the fan systems. If the hot gas bypass is installed, adjust the values to ensure that hot gas is
energized during light load conditions. Increase the
RECYCLE RESTART DELTA T
on the
Service1 table to lengthen the time between restarts.
The machine should not be operated below design minimum load without a hot gas bypass
installed on the machine.