Greenheck Fan 470654 manual Heater Does Not Operate Pilot Ignition

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Troubleshooting

Heater Does Not Operate (Pilot Ignition)

Does not attempt to light (No visible spark)

24 VAC between

terminals W1 and X?

Yes

115 VAC between

terminals 102 and 101?

Yes

115 VAC between

terminals 103 and 101?

Yes

115 VAC between

terminals 104 and 101?

Yes

115 VAC between

terminals 106 and 101?

Yes

Continuity between

terminals 107 and 108?

Yes

No

No

No

No

No

No

Heat switch (S4) off.

Turn heat switch (S4) on.

Heat switch not wired.

Wire heat switch (S4).

Primary fuses blown.

Replace fuses.

Main transformer (TR4) defective.

Replace transformer.

(Optional) inlet air sensor (TS4) holding.

Adjust TS4 setting.

Reference: Start-Up - Blower, Set-Up Optional Components, pg. 15

Heat relay (RH) defective.

Replace heat relay (RH).

The power light on the flame safeguard should

blink approximately every 5 seconds as it

performs a self-diagnostics check.

High limit (HLC1) tripped.

Reset or replace high limit (HLC1).

Check on cause of control loss.

(Optional) high/low gas pressure switch(es)

(PS3 and PS4) tripped.

Correct gas pressure and reset.

Reference: Start-Up - Direct Gas, Check the Pilot Gas Pressure, pg. 15

Airflow switch (PS2) holding for proper airflow.

Correct airflow across burner.

Reference: Start-Up - Direct Gas,

Check the Optional High and Low Gas Pressure Switches, pg. 15

At this time the heater should attempt to light.

The pilot light on the flame safeguard should illuminate.

26Model VSU Make-Up Air

®

Image 26

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 ViewDampers Burner SubassemblyControl Center Installation Service Platform Material List Complete InstallationInstallation of Optional Service Platform Assembly Figure CInstallation of Electrical Wiring Determine the Supply Gas Requirements Installation of Direct Gas PipingInstall Additional Regulator if Required Installation of Building Pressure Control optional Check blower rotation Check for vibration Supply fan RPM Start-Up ChecklistUnit Model Number 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 RateMaxitrol Series 44 9 Terminals The Maxitrol Set the Unit’s Operating TemperatureFlame Signal Check Pilot Ignition Speed Variable Volume OperationOperation 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 Operate Motor 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 LayoutDateTime AM/PM Maintenance LogWarranty