The compressor RUN STATUS parameter on the default screen line now reads PRESTART. If one test
is not successful, the start-up is delayed or aborted. If all the tests are successful, the chilled water pump
relay energizes, and the main screen line now reads STARTUP.
5.3.2. Startup
One second later, the chilled and condenser water pump relays are energized.
Five seconds later the control monitors the chilled water and condenser water flow devices and waits
until the WATER FLOW VERIFY TIME (service-configured, default 5 minutes) expires to confirm water
flow.
After water flow is verified, the water temperature will be compared to CONTROL POINT plus 1/2
CHILLED WATER DEADBAND. If the temperature is less than or equal to this value, the control turns off
the condenser pump relay and goes into a RECYCLE mode.
If the RECYCLE condition is not satisfied, the start-up sequence continues and checks the guide vane
position. For single-stage compressor ( Comp(Single=0,Dual=1)=0 in FACTORY configuration ), if the
guide vanes are more than GUIDE VANE CLOSURE AT STARTUP, the start-up waits until the controller
closes the vanes. For dual-stage compressor (Comp(Single=0,Dual=1)=1 in FACTORY configuration ),
guide vane is to be opened to the initial position “GV1 Closure at Startup” at “Option Configuration”
menu.
If EC valve or Economizer damper valve is equipped and enabled, control checks the status of these
valves position to be fully closed.
If the vanes and valves position are verified.
When chiller type is 19XR, the oil pump pressure difference is less than 6 psi (41.4 kPa), the oil pump
relay will be energized.The control then waits until the oil pressure difference (OIL PRESS VERIFY
TIME, operator-configured, default of 40 seconds) reaches a maximum of 18 psi (124 kPa). After oil
pressure is verified, the control waits 40 seconds for oil prelube.
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