Greenheck Fan 470654 manual Troubleshooting, Blower Does Not Operate

Page 22

Troubleshooting

Blower Does Not Operate

Proper supply power at		No
Proper supply power at		No
main disconnect

	Yes
	Yes

24 VAC between		No
terminals R and X?

	Yes

24 VAC between		No
terminals G and X?

	Yes

24 VAC across		No
terminals 3 and X?
terminals 3 and X?

	Yes

24 VAC across		No
terminals 4 and X?

	Yes

24 VAC across A2 and A1 on		No
supply contactor (ST1)

	Yes

22Model VSU Make-Up Air

Check main voltage.

Reference: Start-Up - Blower, Check the Voltage, pg. 14

Main disconnect (DS1) off.

Turn main disconnect (DS1) on.

Primary fuses blown.

Replace fuses.

Main transformer (TR1) defective.

Replace transformer.

Supply switch (S2) off.

Turn supply switch (S2) on.

Fire system contact (FSC) tripped/not installed.

Correct, replace.

Supply fan overload (ST1 OL) tripped.

Reset and check motor amps.

Reference: Start-Up - Blower, Motor Check, pg. 14

Optional exhaust fan interlocks (ST2-ST5) open.

Correct, replace.

(Optional) freeze protection (RT4) tripped.

Reset.

(Optional) damper limit switch (DL1) holding. Wait for actuator to open fully or adjust limit switch.

(Optional) damper limit switch jumper missing.

Install jumper, reference the units ladder diagram for terminals.

Fan relay (RF) is not energized.

Check for loose connection. Repair or replace relay.

Broken fan belt.

Replace.

Reference: Maintenance - Routine, V-Belt Drives, pg. 31

Defective motor or capacitor.

Repair, replace.

Blown motor fuse.

Replace.

One or more legs of three-phase is out.

Restore missing legs.

At this time the supply contactor (ST1) should pull in, passing power to the supply motor and the blower should start.

®

Image 22

Contents Installation, Operation and Maintenance Manual Model VSU General Safety InformationUnpacking Inspection and Maintenance during StorageReceiving HandlingTable of Contents Product Overview SubassembliesBurner, Blower and Control Center Section Open ViewControl Center Burner SubassemblyDampers Installation Installation of Optional Service Platform Complete InstallationService Platform Material List Assembly Figure CInstallation of Electrical Wiring Install Additional Regulator if Required Installation of Direct Gas PipingDetermine the Supply Gas Requirements Installation of Building Pressure Control optional Unit Model Number Start-Up ChecklistCheck blower rotation Check for vibration Supply fan RPM Start-Up Blower Set-Up Optional Components Check the Optional High and Low Gas Pressure SwitchesStart-Up Direct Gas Check the Supply Gas PressureSet the Maximum Firing Rate Maximum firing rate adjustmentSet the Burner Air Pressure Differential Measuring the Pressure DropRegulators and Modulating Valves Set the Minimum Firing RateFlame Signal Check Pilot Ignition Set the Unit’s Operating TemperatureMaxitrol Series 44 9 Terminals The Maxitrol Speed Variable Volume Operation Operation VAV Units optional ModulatingRecirculation Operation Operation Recirculating Units optionalOperation Electrical Electrical Sequence Exhaust Fan Contact S1 Closed optional3b. Heat Contact S4 Closed Direct Spark Flame Safeguard FSG Sequence3a. Heat Contact S4 Closed Pilot Ignition Heat Contact ClosedTroubleshooting Blower Does Not OperateMotor Overamps Insufficient Airflow Too Much AirflowExcessive Noise or Vibration Heater Does Not Operate Pilot Ignition Does not attempt to light No visible sparkAttempts to light, but no pilot visible spark Visible pilot Between 0.625 and 0.675 in. WC?Heater Does Not Operate Direct Spark Attempts to light, but no flame Visible spark Motors Maintenance RoutineBelt Drives WheelsMaintenance Fall Reference Typical Gas Train Layout with Direct Spark Ignition Heat Relay allows power to pass to heating controls Dirty Filter SwitchFan Relay allows power to pass to energize motor starter Control Center LayoutWarranty Maintenance LogDateTime AM/PM