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CLCH-SVX03C-EN
Troubleshooting
Troubleshooting
This section is intended to be used as a diagnostic aid only. For detailed repair procedures, contact
your local Trane service representative.
WARNING
Hazardous Service Procedures!
The maintenance and troubleshooting procedures recommended in this section of the manual
could result in exposure to electrical, mechanical or other potential safety hazards. Always refer
to the safety warnings provided throughout this manual concerning these procedures. When
possible, disconnect all electrical power including remote disconnect and discharge all energy
storing devices such as capacitors before servicing. Follow proper lockout/tagout procedures to
ensure the power can not be inadvertently energized. When necessary to work with live
electrical components, have a qualified licensed electrician or other individual who has been
trained in handling live electrical components perform these tasks. Failure to follow all of the
recommended safety warnings provided, could result in death or serious injury. including
remote disconnects before servicing. Follow proper lockout/tagout procedures to ensure the
power can not be inadvertently energized. When necessary to work with live electrical
components, have a qualified licensed electrician or other individual who has been trained in
handling live electrical components perform these tasks. Failure to follow all of the
recommended safety warnings provided, could result in death or serious injury.
Table 24. Air handler troubleshooting recommendations
Symptom
Probable Cause
Recommended Action
Bearing is excessively
hot
First start after relubrication (Grease distribution)
Allow machine to cool down and restart.
Over-lubrication
Clean surface of grease and purge.
Over tensioned belts
Adjust belt tension.
No lubricant
Apply lubricant. Check bearings for damage.
Misaligned bearing
Correct alignment. Check shaft level.
Motor fails to start
Blown fuse or open circuit breaker
Replace fuse or reset circuit breaker.
Overload trip
Check and reset overload.
Improper wiring or connections
Check wiring with diagram supplied on unit.
Improper current supply
Compare actual supply power with motor nameplate
recommendations. Contact power company for adjustments.
Mechanical failure
Check that motor and drive rotate freely. Check bearing
lubricant.
Motor stalls
Open phase
Check line for an open phase.
Overloaded motor
Reduce load or replace with larger motor.
Low line voltage
Check across AC line. Correct voltage if possible.
Excessive vibration
Poor alignment
Align bearing set screws (see
Figure 73 on page 85
). Loosen
and retighten bearing set screws.
Shipping spacers not removed
Remove shipping spacers and/or bolts (see the
“Fan
Isolation” section on page 39
).
Over tensioned belts
Adjust belt tension.
Misaligned drive
Align drive.
Motor runs and then
dies down
Partial loss of line voltage
Check for loose connections. Determine adequacy of main
power supply.
Starter shorts when motor warms up
Replace starter.
Motor does not come
up to speed
Low voltage at motor terminals
Check across AC line and correct voltage loss if possible.
Line wiring to motor too small
Replace with larger sized wiring.
Motor overheats
Overloaded motor
Reduce load or replace with a larger motor.
Motor fan is clogged with dirt preventing proper ventilation Remove fan cover, clean fan and replace cover.
Excessive motor noise
Motor mounting bolts loose
Tighten motor mounting bolts.
Rigid coupling connections
Replace with flexible connections.
Worn motor bearings
Replace bearings and seals.
Fan rubbing on fan cover
Remove interference in motor fan housing.
Rapid motor bearing
wear
Excessive overhung load due to overtensioned drive
Check belt tension and overhung load.
Excessive overhung load due to a small diameter motor
sheave
Replace sheave with larger one.