Sterlco S Series Central Chilling Stations - Manual (Page 35)

SCW Series Central Chilling Stations Page 35 of 77
; Complete all piping leading to and from the pump tank.
Observe all applicable codes.
; Complete all electrical wiring. Observe all applicable codes.
; Prepare all related equipment in the system for operation.
; Check for proper compressor rotation direction. To confirm
proper rotation:
1. Connect a phase meter and phase incoming power
ABC.
2. Connect a refrigerant gauge to the suction service
valve. Fully front seat the service valve and open one
full turn.
3. Bump start the compressor by switching off then on
quickly 0.5 to 1 second. If the rotation is correct, the
suction pressure will drop immediately. A rise in
pressure will indicate the wrong rotation. If this occurs,
change over two electrical phases of the incoming
power supply (do not change phase at the compressor
starter).
Note:
• Never switch contactor leads or motor leads for reversing
rotation.
• Do not use contactor or motor leads for phase matching.
• Compressor damage will occur if the compressor is run in
reverse. The compressor motor protector checks for correct
phasing and will not allow it to start in reverse.
• If you discover that compressor rotation is reversed, correct
it by switching any two main power leads into the
disconnect switch or distribution block on the unit.
; Open the 1” (approx. 25 mm) makeup water valve and allow
the tank to fill until the automatic float valve shuts off. The
float level should be adjusted so the standing water level is 8”
(20 cm) from the top of the tank.
; Close the discharge butterfly valve, crack it open, then start the
pump and observe the gauge.
; Check for proper pump rotation direction. To confirm proper
rotation:
1. Observe a pump pressure gauge connected to the
suction and discharge sides of the pump casing through
two ¼” (approx. 6.4 mm) gauge cocks.