MUA-SVX005B-EN
37
Problem
Probable
Cause
Solution
Blower Wheel
1. Loose on shaft
2. Defective blower wheel. Do not run blower.
Contact manufacturer.
3. Unbalanced.
4. Worn as a result of contact with abrasive or
corrosive material.
Housing
1. Foreign material in housing.
2. Cutoff of other part loose (rattling during
operation).
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
wheel, bearings or pulley.
3. If more than two bearings are on a shaft,
they must be properly aligned.
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
application.
Obstruction in High
Velocity Air Stream
may cause Rattle
or Pure Tone
Whistle
1. Dampers.
2. Registers.
3. Grilles.
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
pulsations.
Rattles and/or
Rumbles
1. Vibrating duct work.
2. Vibrating cabinet parts.
3. Vibrating parts not isolated from building.
CFM Low -
Insufficient Air
Flow
Blower
1. Forward curved blower wheel installed
backwards.
2. Blower operating backwards.
3. Cutoff missing or improperly installed.
4. Blower wheel RPM too low.
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Summary of Contents for GGAA
Page 35: ...MUA SVX005B EN 35 Figure 12 Blower RPM Adjustment M Ma ai in nt te en na an nc ce e ...
Page 47: ...MUA SVX005B EN 47 Motor Electric Data Table 7 Full Load Current in Amperes ...
Page 50: ...50 MUA SVX005B EN Coil Cabinet Dimensional Data Figure 13 Coil Cabinet Dimensional Data ...
Page 57: ...MUA SVX005B EN 57 Gas Equipment Start Up ...
Page 58: ...58 MUA SVX005B EN N No ot te es s ...