Trane UCCA Installation, Operation And Maintenance Manual page 63

Table 21. Air handler troubleshooting recommendations
Symptom Probable Cause
Poor alignment
Bearing noise
Failed bearing
Inadequate lubrication
Incorrect airflow
Incorrect water flow
Low water coil
Incorrect water temperature
capacity
Coil is piped incorrectly
Dirty fin surface
Incorrect glycol mixture
Incorrect airflow
Expansion valve is not operating properly or is sized
incorrectly
Incorrect refrigerant charge
Condensing unit failure
Low refrigerant Coil is piped incorrectly
coil capacity
Clogged refrigerant line filter
Failure of suction/liquid line components
Dirty fin surface
Fin frosting
Incorrect airflow
Coil is piped incorrectly
Incorrect steam pressure
Low steam coil
Excessive steam superheat
capacity
Failure of steam line/condensate return components
Boiler failure
Dirty fin surface
Plugged Drain Line
Drain pan is
Unit not level
overflowing
Improper trap design
Improper trap design
Standing water
Unit not level
in drain pan
Plugged drain line
Coil face velocity too high
Improper trap design
Wet interior
Drain pan leaks/overflows
Condensation on surfaces
Missing filters
Excess dirt in
unit
Filter bypass
Microbial growth
(mold) inside air Standing water in drain pan
handler
CLCH-SVX009A-EN
Recommended Action
Loosen bearing set screws and realign (see
Sheaves," page 53)
Replace bearing.
Replace bearing.
Check fan operating condition.
Inspect the water pumps and valves for proper operation and check the
lines for obstructions.
Adjust the chiller or boiler to provide the proper water temperature.
Verify coil piping (see "Coil Piping and Connections," page
Clean the fin surface (see the
Verify glycol mixture and adjust if necessary.
Check fan operating condition.
Check sensing bulb temperature.
Verify valve operation.
Verify proper valve size.
Verify refrigerant charge and adjust if necessary.
Verify condensing unit operation.
Verify coil piping (see "Coil Piping and Connections," page
Change filter core.
Verify component operation
Clean the fin surface (see the
Do not use steam to clean refrigerant coils.
Verify defrost cycle operation.
Verify frostat operation.
Verify refrigerant charge.
Check fan operating condition.
Verify coil piping (see "Coil Piping and Connections," page
Verify steam pressure and adjust if necessary.
Check steam superheat.
Steam superheat should not exceed 50ºF.
Verify component operation
Verify boiler operation
Clean the fin surface (see the
Clean drain line
Level unit
Design trap per unit installation instructions
Design trap per unit installation instructions
Level unit
Clean drain line
Reduce fan speed
Design trap per unit installation instructions
Repair leaks
Insulate surfaces
Replace filters
Reduce filter bypass by ensuring all blockoffs are in place.
See "Standing water in drain pan" above
Troubleshooting
"Align Fan and Motor
30).
"Coils" section on page 55).
30.)
"Coils" section on page 55).
30).
"Coils" section on page 55).
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