Sterlco S Series Central Chilling Stations - Manual (Page 25)

SSC Series Central Chilling Stations Page 25 of 86
SSC Series condensing pressure
with 95ºF (35ºC) condenser air
R-22 = 260 psi (1,793 kPa/17.93 bars)
Note: Due to the variables involved in remote air-cooled condenser installations, no set or
standard piping procedure exists. Each installation must be designed and installed by
qualified persons. Follow the instructions supplied with the condenser.
3-11 Checking Motor Direction
Compressor
Note:
• Never switch contactor leads or motor leads for reversing
rotation.
• Do not use contactor or motor leads for phase matching.
• Compressor noise from reverse rotation is noticeable. Do not
run in this mode for more than ten (10) seconds. The
compressor shuts off if run longer in this mode.
• Reverse rotation can cause suction and discharge pressures to
be approximately equal; amp draws will be lower than normal.
• 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.
Water Pump
A positive pressure of 20 to 30 psi (137.9 to 206.8 kPa/1.38 to 2.07
bars) on the
TO PROCESS line indicates correct pump rotation.
Condenser Fan
On SSC Series remote air-cooled units, air should draw through
the condenser and discharge up from the condenser.
Changing fan rotation direction
• Disconnect and lock out power at the fused disconnect.
• If all fans are going backwards, reverse any two main power
leads.
• If only some of the fans are going backwards, switch any two of
their respective motor leads.