Troubleshooting
CLCH-SVX009J-EN
75
Bearing noise
Poor alignment
Loosen bearing set screws and realign (see
)
Failed bearing
Replace bearing.
Inadequate lubrication
Replace bearing.
Low water coil
capacity
Incorrect airflow
Check fan operating condition.
Incorrect water flow
Inspect the water pumps and valves for proper operation and check the
lines for obstructions.
Incorrect water temperature
Adjust the chiller or boiler to provide the proper water temperature.
Coil is piped incorrectly
“Coil Piping and Connections,” p. 38
).
Dirty fin surface
Clean the fin surface (see
).
Incorrect glycol mixture
Verify glycol mixture and adjust if necessary.
Low refrigerant
coil capacity
Incorrect airflow
Check fan operating condition.
Expansion valve is not operating properly or is sized
incorrectly
Check sensing bulb temperature.
Verify valve operation.
Verify proper valve size.
Incorrect refrigerant charge
Verify refrigerant charge and adjust if necessary.
Condensing unit failure
Verify condensing unit operation.
Coil is piped incorrectly
“Coil Piping and Connections,” p. 38
.)
Clogged refrigerant line filter
Change filter core.
Failure of suction/liquid line components
Verify component operation
Dirty fin surface
).
Do not use steam to clean refrigerant coils.
Fin frosting
Verify defrost cycle operation.
Verify frostat operation.
Verify refrigerant charge.
Low steam coil
capacity
Incorrect airflow
Check fan operating condition.
Coil is piped incorrectly
“Coil Piping and Connections,” p. 38
).
Incorrect steam pressure
Verify steam pressure and adjust if necessary.
Excessive steam superheat
Check steam superheat.
Steam superheat should not exceed 50ºF.
Failure of steam line/condensate return components
Verify component operation
Boiler failure
Verify boiler operation
Dirty fin surface
).
Drain pan is
overflowing
Plugged Drain Line
Clean drain line
Unit not level
Level unit
Improper trap design
Design trap per unit installation instructions
Standing water
in drain pan
Improper trap design
Design trap per unit installation instructions
Unit not level
Level unit
Plugged drain line
Clean drain line
Wet interior
Coil face velocity too high
Reduce fan speed
Improper trap design
Design trap per unit installation instructions
Drain pan leaks/overflows
Repair leaks
Condensation on surfaces
Insulate surfaces
Excess dirt in
unit
Missing filters
Replace filters
Filter bypass
Reduce filter bypass by ensuring all blockoffs are in place.
Microbial growth
(mold) inside air
handler
Standing water in drain pan
See “Standing water in drain pan” above
Table 22. Air handler troubleshooting recommendations (continued)
Symptom
Probable Cause
Recommended Action