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Maintenance
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AH-SVX008C-EN
Noisy Compressor
a. Expansion valve stuck in open position
(abnormally cold suction line).
Ensure feeder bulb is tight on suction line.Check
operation and superheat.
b. Worn or scarred compressor bearings.
Replace compressor.
c. Liquid slugging.
System overcharged. Reclaim excess refrigerant.
d. Scroll compressor not properly phased.
Phase correctly at main power source. Do not
rewire compressor.
Compressor Fails to Start
a. Temperature set point too high.
Adjust to desired temperature.
b. Compressor internal overload protector is
open.
Check compressor for short circuit or ground.
c. Complete loss of refrigerant charge (low
pressure safety switch).
Locate and repair leak. Recharge system.
d. Condenser pressure too high (high pres- sure
safety switch).
Check condenser for obstructions.
e. Condensate switch open.
1. Ensure unit is level.
2. Check that condensate pan is draining
properly. Clear obstructions.
System Short of Capacity
a. Low refrigerant (indicated by bubbles in sight
glass).
Check for leaks. Repair and recharge system.
b. Expansion valve stuck or obstructed (short
cycling or continuous running).
Remove valve and clear obstruction or replace
valve.
c. Clogged drier/strainer (feels cold).
Replace with new drier/strainer.
d. Reduced airflow
Check belt tension, filters and clear evaporator
coil of debris.
Compressor Short Cycles
a. Low line voltage causing compressor to
overheat.
Check power source for cause of low line voltage.
b. Dirty or iced over evaporator coil.
Defrost and/or clean coil.
c. Reduced airflow (when applicable).
Check filter and belt tension.
d. Lack of refrigerant.
Check for leak. Repair and recharge system.
e. Short cycling of conditioned air.
1. Supply and/or return grilles are incorrectly
oriented. Re-orient.
2. Supply and return grilles are too close
together. Move farther apart.
3. Insufficient heat load. Add temporary heat
load to compensate.
f. Thermostat is improperly located.
Check for supply registers that may be too close
to thermostat. Relocate if necessary.
Heater Inoperative
a. Fuses blown/circuit breaker tripped.
Check for short circuit; replace fuses/reset circuit
breaker.
b. Thermostat set too low.
Increase temperature setpoint.
c. Overheat switch open due to insufficient
airflow across heater elements.
Check for dirty filters or obstructions that may
reduce airflow. Correct or replace as needed.
d. Fuse link blown.
Replace fuse link (see item immediately
above).
e. Heater element burned out.
Check continuity with an ohmmeter. Replace
heater element.
Table 10. Troubleshooting methods (continued)
Symptom
Probable Cause
Recommendation
Summary of Contents for CeilAir CW
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