Carrier PC211 specifications Start-Up/Shutdown/Recycle Sequence Figure, Local Start-Up

Start-Up/Shutdown/Recycle Sequence (Figure 24)

Local Start-Up

Local start-up (or a manual start-up) is initiated by pressing the LOCAL menu softkey which is on the default LID screen. Local start-up can proceed when Time Schedule 01 is in OCCUPIED mode, and after the internal 15 minute start-to-start and the 3 minute stop-to-start inhibit timers have expired (on PSIO software Version 08 and lower or a 1 minute stop-to-start timer on PSIO Software Version 09 and higher).

The chiller start/stop status point on the Status01 table may be overridden to start, regardless of the time schedule, in order to locally start the unit. Also, the remote contacts may be enabled through the LID and closed to initiate a start-up.

Whenever the chiller is in LOCAL control mode, the PIC will wait for Time Schedule 01 to become occupied and the remote contacts to close, if enabled. The PIC will then perform a series of pre-start checks to verify that all pre-start alerts and safeties are within the limits shown in Table 3. The run status line on the LID now reads ‘‘Starting.’’ If the checks are successful, the chilled water/brine pump relay will be energized. Five seconds later, the condenser pump relay is energized. Thirty seconds later the PIC monitors the chilled water and condenser water flow switches, and waits until the WATER FLOW VERIFY TIME (operator configured, default 5 minutes) to confirm flow. After flow is verified, the chilled water/brine temperature is compared to CONTROL POINT plus DEADBAND. If the temperature is less