York Millennium YDAS 410 Installation Operation & Maintenance page 133

PROBLEM
Compressor Won't Load
Lack of Cooling Effect
"PHASE ROTATION" FAULT
"MOTOR CURRENT
UNBALANCE"
CAUSE
1. Demand not great enough.
2. Low oil pressure.
3. Defective water
temperature sensor.
1. Fouled evaporator surface.
Low suction pressure
will be observed.
2. Improper flow through the
evaporator.
3. Low refrigerant charge.
Low suction pressure
will be noted.
1. Chiller wiring phased
incorrectly.
1. Incoming voltage not
balanced phase to phase.
SOLUTION
1. No problem. Consult
Installation Manual to aid
in understanding
compressor operation.
2. Check oil circuit.
Assure oil load solenoid
valve is working.
Assure that discharge
pressure is at least
50 pounds over suction.
Contact the local YORK
service representative.
3. Compare the display with
a thermometer. Should be
within + or - 2 degrees.
1. Contact the local YORK
service representative.
2. Reduce flow to within
chiller design specs.
3. Check subcooling and
add charge as needed.
1. Rewire chiller wiring.
1. Resolve incoming voltage
imbalance.