80 TGZ 040A through TGZ 190A OMM TGZ-1
Troubleshooting Chart
PROBLEM POSSIBLE CAUSES POSSIBLE CORRECTIVE STEPS
Compressor Will
Not Run
1. Main switch, circuit breakers open.
2. Fuse blown.
3. Thermal overloads tripped or fuses
blown.
4. Defective contactor or coil.
5. System shut down by equipment
protection devices.
6. No heating required.
7. Liquid line solenoid will not open.
8. Motor electrical trouble.
9. Loose wiring.
1. Close switch
2. Check electrical circuits and motor
winding for shorts or grounds.
Investigate for possible overloading.
Replace fuse or reset breakers after
fault is corrected.
3. Overloads are auto reset. Check unit
closely when unit comes back on lines.
4. Repair or replace.
5. Determine type and cause of shutdown
and correct it before resetting safety
switch.
6. None. Wait until unit calls for heating.
7. Repair or replace coil.
8. Check motor for opens, short circuit, or
burnout.
9. Check all wire junctions. Tighten all
terminal screws.
Compressor
Noisy or Vibrating
1. Flooding of refrigerant into crankcase.
2. Improper piping support on suction or
liquid line.
3. Worn compressor.
1. Check superheat setting of expansion
valve.
2. Relocate, add or remove hangers.
3. Replace.
High Discharge
Pressure
1. Condenser water insufficient or
temperature too high.
2. Fouled condenser tubes
3. Noncondensables in system.
4. System overcharge with refrigerant.
5. Discharge shutoff valve partially closed.
6. Condenser undersized.
1. Investigate ways to increase hot water
supply or lower the temperature of the
hot water. Check operation of the
supplementary heater.
2. Clean.
3. Purge the noncondensables.
4. Remove excess refrigerant.
5. Open valve.
6. Check condenser rating tables against
the operation.
Low Discharge
Pressure
1. Suction shutoff valve partially closed.
2. Insufficient refrigerant in system.
3. Low suction pressure.
4. Compressor operating unloaded.
5. Condenser too large.
.
1. Open valve.
2. Check for leaks. Repair and add charge.
3. See corrective steps for low Suction
pressure below.
4. See corrective steps for failure of
compressor to load.
5. Check condenser rating table against
the operation.
High Suction
Pressure
1. Excessive load.
2. Expansion valve overfeeding.
3. Compressor unloaders open.
1. Reduce load or add additional
equipment.
2. Check remote bulb. Regulate superheat.
3. See corrective steps for failure of
compressor to load.
Low Suction
Pressure
1. Lack of refrigerant.
2. Evaporator dirty.
3. Clogged liquid line filter-drier.
4. Clogged suction line or compressor
suction gas strainers.
5. Expansion valve malfunctioning.
6. Condensing temperature too low.
7. Insufficient water flow.
1. Check for leaks. Repair and add charge.
2. Clean chemically.
3. Replace cartridge(s).
4. Clean strainers.
5. Check and reset for proper superheat.
Replace if necessary.
6. Check means for regulating condensing
temperature.
7. Adjust flow.
Compressor will
Not Unload or
Load Up
1. Defective capacity control.
2. Faulty thermostat stage or broken
capillary tube.
3. Stages not set for application.
1. Replace
2. Replace
3. Reset thermostat setting to fit
application.
Compressor
Loading/Unloadin
g Intervals Too
Short
1. Erratic water thermostat.
2. Insufficient water flow.
1. Replace
2. Adjust flow.
Table continued on next page.
To Next Page
Loading...
Need help?
General