compressor is running in a lightly loaded condi ti on. This cycling of the ch ill er is normal and is
known as recycle. A recycle shutdown is initiated when any of the following conditions are true:
when in LCW co ntrol, the
LEAVING CHILLED WATER
temperature is more than 5° F
(3° C) below the control poin t, and the
CONTROL PO INT
has not incre ased 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 la st 5 minutes
when the
LEAVING CHILLED WATER
temperature is wit hin 3° F (2° C) of the
BRINE
REFRIG TRIPPOINT.
When the machine is in RECYCLE mode, the chil led water pump relay remains energized so
that the chilled water temperature can be monitored for increasing load. The recycle control
uses
RECYCLE RESTART DELT A 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 Servic e1 table. The co mpressor will r estart when:
in LCW CONTROL the
LEAVING CHILLED WATER
temperature is great er than the
CONTROL POINT
plus the
RECYCLE RESTART DELTA T
; or
in ECW CONTROL, the
ENTERING CHILLED W ATER
temperature is greater th an
the
CONTROL POINT
plus the
RECYCLE RESTART DELTA T
Once these conditions are met, the compressor sha ll initiate a start-up, with a normal start-up
sequence.
An alert condition may be generated if 5 or more RECYCLE STARTUPs occur in le ss than 4