Checking Motor Direction; Changing Fan Rotation Direction; Initial Start-Up; Pre-Startup Checks - AEC A0551794 RS Series Manual

Checking Motor Direction

Compressor
Caution!
Note:
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 central chillers with remote air-cooled units, air should draw through the condenser and
discharge up from the condenser.

Changing fan rotation direction

3-5

Initial Start-up

Pre-Startup Checks

Note: These lists assume the installation information in this manual have been read
Screw Compressor Central Chiller
Check Compressor Rotation Before Starting Unit!
Connect a phase monitor and phase incoming power ABC.
Unit must be wired in sequence (ABC) and checked before start up.
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 phasing is reversed, correct it by switching any
two main power leads into the disconnect switch or distribution
block on the unit.
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.
and followed.
Have new chillers started up and checked by a qualified refrigeration
service technician.
The manufacturer offers factory startup for your Screw Compressor Central
Chiller. Call the Manufacturers' Service Department at for more details.
Chapter 3: Installation 28