Trane CLCH-IM-16A Installation And Maintenance Manual page 70

Table 52
T-Series Climate Changer Trouble Analysis
SYMPTOM
Motor runs and then dies down
Motor does not come up to
speed
Motor overheats
Excessive motor noise
Rapid motor bearing wear
Loose fan belt
Shorter belt life
Bearing noise
Low coil capacity
(Chilled water)
Low coil capacity (Refrigerant)
Installation and Maintenance
PROBABLE CAUSE
Partial loss of line voltage
Stator shorts when motor warms up
Low voltage at motor terminals
Line wiring to motor too small
Overloaded motor
Motor fan is clogged with dirt
preventing proper ventilation
Motor mounting bolts loose
Rigid coupling connections
Worn motor bearings
Fan rubbing on fan cover
Excessive overhung load due to
overtensioned drive
Excessive overhung load due to a
small diameter motor sheave
Motor is poorly positioned
Worn or damaged belt
Worn sheaves
Worn sheaves
Misaligned belt
Grease or oil on belts
Belt slipping
Belts rubbing
Poor alignment
Inadequate lubrication
Air is bypassing coil
Coil tubes are blocked
Incorrect airflow
Incorrect gpm
Incorrect water temperature
Air is bypassing coil
Coil tubes are blocked
Incorrect airflow
Expansion valve not operating
RECOMMENDED ACTION
Check for loose connections.
Determine adequacy of main power
supply.
Replace stator.
Check voltage across AC line and
correct voltage loss if possible.
Replace with larger sized wiring.
Reduce load or replace with a larger
motor.
Remove fan cover, clean fan and
replace cover.
Tighten motor mounting bolts.
Replace with flexible connections.
Replace bearings and seals.
Remove interference in motor fan
housing.
Check belt tension and overhung load.
Replace sheave with larger one.
Adjust belt tension.
Replace belt or belt set. Check sheave
alignment.
Replace sheaves.
Replace sheaves.
Realign drive with MVP sheave set at
mean pitch diameter.
Check for leaky bearings. Clean belts
and sheaves.
Adjust tension.
Remove obstruction or realign drive
for clearance.
Loosen bearing set screws and realign
(See Figure 50 .)
Grease bearing(s).
Prevent bypass with block-offs.
Clean and unblock tubes.
Check fan operating conditions.
Check water pumps, valves and lines
for obstructions.
Provide proper water temperature.
Prevent bypass with block-offs.
Clean and unblock tubes.
Check fan operating conditions.
Check sensing bulb location and TXV
operation.
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