ATS CyberChiller Series - Manual (Page 31)

(©October, 2006)
CyberChiller Series Installation, Operation & Maintenance Manual
4-4
SYMPTOM PROBABLE CAUSE RECOMMENDATION
Head Pressure is too Low a. Loss of refrigerant (indicated by Repair leak and recharge system.
bubbles in the sight glass).
Suction Pressure too Low a. Expansion valve stuck in the open Repair or replace valve.
position (indicated by abnormally cold
suction line).
b. Low charge, flash gas in liquid line Repair leak and recharge system.
(indicated by bubbles in sight glass).
c. Clogged drier/strainer (feels cool to Replace drier/strainer.
the touch).
d. Obstructed expansion valve (indicat Replace valve.
ed by loss of capacity).
e. Loss of control fluid from expansion Replace valve or control head.
valve control head (indicated by
bubbles in the sight glass).
Compressor Fails to Start a. Temperature setpoint too high. Adjust to desired temperature.
b. Compressor internal protector Check compressor for short circuit or
is open. ground.
c. Complete loss of refrigerant charge Locate and repair leak. Recharge
(low pressure safety switch). system.
d. Condenser pressure too high (high Check condenser for obstructions.
pressure safety switch).
e. Minimum off time has not expired. Wait for time to expire.
System Short of Capacity a. Low refrigerant (indicated by Check for leaks Repair and recharge
bubbles in sight glass). system.
b. Expansion valve stuck or Remove valve and clear obstruction or
obstructed (short cycling or replace valve.
continuous running).
c. Clogged drier/strainer (feels cold). Replace with new drier/ strainer.
Compressor Short Cycles a. Low line voltage causing Check power source for cause of low
compressor to overheat. line voltage.
b. Reduced flow rate. Check pump and strainer.
c. Lack of refrigerant Check for leak. Repair and recharge
system.