Greenheck Fan 45 Manuel D’Utilisation

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* Always provide the unit model and serial number when requesting parts or service information. * Always check motor amps and compare to nameplate rating.
Control power (24 Vac) wiring 
run is too long (resistance 
should not exceed 0 .75 ohms) .
Shorten wiring run to mechanical room or install a relay 
which will turn unit on/off (C/F for relay information) .
Incoming supply power is 
less than anticipated . Voltage 
supplied to starter coil must 
be within +10% / -15% of
nominal voltage stated on 
the coil .
Need to increase supply power or use a special control
transformer which is sized for the actual supply power .
Motor Starters 
‘Chatter’
or 
Do Not Pull In
Blown fuse or open circuit 
breaker .
Replace fuse or reset circuit breaker and check amps .
Possible Cause
Symptom
Corrective Action
Defective motor or capacitor .
Replace .
Motor starter overloaded .
Reset starter and check amps .
Electrical .
Check for On/Off switches . Check for correct supply voltage .
Drive .
Check for broken or loose belts . Tighten loose pulleys .
Blower Fails to 
Operate
Cfm too high .
Check cfm and adjust drives if needed .
Static pressures are higher or 
lower than design .
If higher, ductwork should be improved .
If lower, fan rpm should be lower .
Blower rotation is incorrect .
Check rotation and reverse if necessary .
Motor voltage incorrect .
Check motor nameplate versus supplied voltage .
Motor horsepower too low .
See specifications and catalog for fan curves to determine if 
horsepower is sufficient .
Motor Over Amps
Shorted windings in motor .
Replace motor .
Unit damper not fully open .
Adjust damper linkage or replace damper motor .
System static pressure too high
Improve ductwork to eliminate losses using good duct 
practices .
Blower speed too low .
Check for correct drives and rpm with catalog data .
Fan wheels are operating 
backwards .
For 3-phase, see Direction of Fan Wheel Rotation under Unit 
Start-Up section .
Dirty filter or energy wheel .
Follow cleaning procedures in Routine Maintenance section .
Leaks in ductwork .
Repair .
Elbows or other obstructions 
may be obstructing fan outlet .
Correct or improve ductwork .
Belt slippage .
Adjust belt tension .
Blower fan speed too high .
Check for correct fan rpm . Decrease fan speed if necessary .
Filter(s) not in place .
Install filters .
Insufficient static pressure (Ps) 
(airflow resistance) .
Induce Ps into system ductwork . Make sure grilles and 
access doors are installed . Decrease fan speed if necessary .
Low Airflow (cfm)
High Airflow (cfm)
Troubleshooting