Operation Features:

2 chiller lead/lag

addition of a third chiller for backup

manual rotation of lead chiller

load balancing if configured

staggered restart of the chillers after a power failure

chillers may be piped in parallel or in series chilled water flow

Common Point Sensor Installation

Lead/lag operation does not require a common chilled water point sensor. Common point

sensors can be added to the 8-input option module, if desired. Refer to the certified drawings for termination of sensor leads.

Note: If the common point sensor option is chosen on a chilled water system, both machines should have their own 8-input option module and common point sensor installed. Each machine will use its own common point sensor for control, when that machine is desig- nated as the lead chiller. The PIC cannot read the value of common point sensors installed on other machines in the chilled water system.

When installing chillers in series, a common point sensor should be used. If a common point sensor is not used, the leaving chilled water sensor of the upstream chiller must be moved into the leaving chilled water pipe of the downstream chiller.

If return chilled water control is required on chillers piped in series, the common point return

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Carrier PC211 specifications Common Point Sensor Installation