York Millennium YK M3 M3 G4 THRU YK S6 S4 J2 - Manual (Page 47)

YORK INTERNATIONAL 47
FORM 160.49-O2
TABLE 2 – OPERATING ANALYSIS CHART
RESULTS POSSIBLE CAUSE REMEDY
1. SYMPTOM: ABNORMALLY HIGH DISCHARGE PRESSURE
Temperature difference between liquid Air in condenser.
refrigerant out and water off condenser
higher than normal.
High discharge pressure. Condenser tubes dirty or . Clean condenser tubes. Check water
scaled conditioning.
High condenser water Reduce condenser water inlet
temperature. temperature. (Check cooling tower
and water circulation.)
Temperature difference between conden- Insufficient condensing Increase the quantity of water through
ser water on and water off higher than water flow. the condenser to proper value.
normal, with normal cooler pressure.
2. SYMPTOM: ABNORMALLY LOW SUCTION PRESSURE
Temperature difference between leaving Insufficient charge of Check for leaks and charge
chilled water and refrigerant in cooler refrigerant. refrigerant into system.
greater than normal with high discharge
Flow orifice blocked. Remove obstruction.
temperature.
Temperature difference between leaving Cooler tubes dirty or Clean cooler tubes.
chilled water and refrigerant in the cooler restricted.
greater than normal with normal discharge
temperature.
Temperature of chilled water too low with Insufficient load for Check prerotation vane motor opera-
with low motor amperes. system capacity. tion and setting of low water temper-
ature cutout.
3. SYMPTOM: HIGH COOLER PRESSURE
High chilled water temperature. Prerotation vanes fail to Check the prerotation vane motor
open. positioning circuit.
System overload. Be sure the vanes are wide open
(without overloading the motor) until
the load decreases.
4. SYMPTOM: NO OIL PRESSURE WHEN SYSTEM START BUTTON PUSHED
Low oil pressure displayed on control Oil pump running in wrong Check rotation of oil pump
center; compressor will not start. direction. (Electrical Connections).
Oil pump not running. Check electrical connections to oil
pump and press manual reset on oil
pump starter mounted on condenser
shell.
5. SYMPTOM: COMPRESSOR STARTS, NORMAL OIL PRESSURE DEVELOPS, FLUCTUATES FOR
SHORT WHILE, THEN COMPRESSOR STOPS ON OIL PRESSURE CUTOUT
Oil pressure normal, fluctuates then Unusual starting conditions Drain the oil from the compressor and
compressor stops on Oil Pressure exist, i.e., oil foaming in charge new oil into the compressor.
Cutout. Display reading resevoir and piping due to (Refer to “Charging The System With
LOW OIL PRESSURE .
lowered system pressure. Oil”, page 39.)
Burned out oil heater. Replace oil heater.