Trane GGAA Installation, Operation And Maintenance Manual page 37

Problem
CFM Low -
Insufficient Air
Flow
MUA-SVX005B-EN
Probable Solution
Cause
Blower Wheel
1. Loose on shaft
2. Defective blower wheel. Do not run blower.
3. Unbalanced.
4. Worn as a result of contact with abrasive or
Housing
1. Foreign material in housing.
2. Cutoff of other part loose (rattling during
Electrical
1. Lead-in cable not secure.
2. AC hum in motor or relay
3. Starting relay chatter.
4. Noisy motor bearings.
5. Single phasing a 3–phase motor.
Shaft
1. Bent.
2. Undersized. May cause noise at blower
3. If more than two bearings are on a shaft,
High Air Velocity
1. Duct work too small for application.
2. Blower selection too small for application.
3. Registers or grilles too small for application.
4. Cooling coil with insufficient face area for
Obstruction in High
1. Dampers.
Velocity Air Stream
2. Registers.
may cause Rattle
or Pure Tone
3. Grilles.
Whistle
4. Sharp elbows.
5. Sudden expansion in duct work.
6. Sudden contraction in duct work.
7. Turning vanes.
Pulsation or Surge
1. Blower too large for application.
2. Ducts vibrate at same frequency as blower
Rattles and/or
1. Vibrating duct work.
Rumbles
2. Vibrating cabinet parts.
3. Vibrating parts not isolated from building.
Blower
1. Forward curved blower wheel installed
2. Blower operating backwards.
3. Cutoff missing or improperly installed.
4. Blower wheel RPM too low.
Contact manufacturer.
corrosive material.
operation).
wheel, bearings or pulley.
they must be properly aligned.
application.
pulsations.
backwards.
T T r r o o u u b b l l e e s s h h o o o o t t i i n n g g
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