Greenheck Fan 470656 manual Modulating Furnace Will Not Light

Page 51

Troubleshooting

2:1 Modulating Furnace Will Not Light

24 VAC across R and X?

Yes

24 VAC across W1 and X?

Yes

24 VAC across S and T?

Yes

24 VAC across C and T?

Yes

24 VAC across A and T?

Yes

Ignition controller (IC#) red LED

blinks 7 times or is on

No

Ignition controller (IC#) red LED

blinks 6 times

No

Ignition controller (IC#) red LED blinks

1 time, 2 times or 4 times

Yes

Everything is working

properly, consult factory.

No

No

No

No

No

Yes

Yes

Yes

Main disconnect (DS1) open or defective

Close, repair or replace

Main transformer (TR1) fault

Replace main transformer

Heat switch (S4) open or not wired

Close or replace heat switch (S4)

Heat transformer (TR5) fault

Replace heating transformer

Discharge temperature was above high limit control (HLC1)

Wait for high limit to cool and reset.

Optional inlet air sensor contact (TS4 open)

Adjust setting reference Blower Start-Up, Step #6

Heat relay (RH) is not energized

Check for loose connections. Repair or replace heat relay (RH)

Discharge air selector (TS3) improperly set or faulty

Adjust setting (see staged start-up) or replace sensor

Ignition controller (IC1) failed

(Replace ignition controller)

Combustion blower (CM) not functioning

Replace combustion blower or relay (CM)

Air proving switch (PS2) defective

Replace air proving switch

Improper manifold pressure

Set high and low manifold pressure (refer to the 2:1 Electronic

Modulation Start-Up section)

Faulty spark rod or spark gap does not equal 1/8 inch

Replace spark rod or adjust gap to 1⁄8 inch

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Model IG / IGX Make-Up Air 51

Image 51

Contents General Safety Information Installation, Operation and Maintenance ManualStorage Inspection and Maintenance during StorageReceiving HandlingClearance to Combustibles / Service Clearances Table of ContentsInstallation of Arrangement DB / HZ Installation of Indoor UnitAssemble and Attach Weatherhood Installation of Roof Mounted Unit Arrangement DBCInstall Combination Curb Adaptor Install Curb/Equipment SupportsInstall Exhaust Fan Install Exhaust OptionsInstall Supply Unit Installation of Venting for Outdoor Units Installation of Evaporative Cooling Module optionalSeparated Combustion Concentric Venting Installation of Venting for Indoor UnitsVenting Methods Standard Indoor VentingInstallation of Standard Indoor Venting Installing Exhaust Vent PipeVent Pipe Diameter Concentric Venting Horizontal Installation of Concentric Venting GeneralConcentric Venting Vertical Intake END Seal Wall Openings Installation of Two Pipe Venting HorizontalSeal Roof Penetration Installation of Two Pipe Venting VerticalInstallation Electrical Wiring Install DDC Interface Optional Wire the Evaporative Cooler optionalInstall Economizer Sensors optional Install Discharge Air Sensor optionalConnect the Supply Gas Line Installation of Gas PipingInstall Additional Regulator if Required Determine the Supply Gas RequirementsCheck/Adjust Water Level Installation Evaporative Cooler Piping optionalInstall the Water Supply Line Install the Drain LineWater Wizard Valves When provided by manufacturer Installation of Water WizardTM optionalInstall Normally Closed Supply Line/ Solenoid Install Normally Open Drain Line/ SolenoidWire the Temperature Sensor Installation of Water WizardInstallation Direct Expansion DX Coil Piping optional Wire the SolenoidsEvacuate and Charge the Coil Install Suction LineMount the Remote Sensing Bulb By Others Check Coil Piping for LeaksInstallation of Building Pressure Control optional Installation of Chilled Water Coil Piping optionalStart-Up Blower Set-up Optional Components Send Unit to High Fire Reset the Temperature SettingStart-Up Furnaces all units Start-Up Single Stage ControlCheck the Low Fire Manifold Pressure Start-Up 21 Staged ControlStart-Up 81 Staged Control Send Unit to Low FireAccess the Inlet Air Sensor Setting Access the Setpoints MenuAccess the Discharge Air Temperature Setting Edit the SettingAccess the Room Override Setting Start-Up 21 Electronic Modulation High Fire AdjustmentExit High Fire Mode Start-Up 41 Electronic ModulationCheck the Low Fire Manifold Pressures Access the Setpoints Menu Set the Enthalpy Changeover Set Point optional Verify Sensor InstallationStart-Up Economizer optional Set Minimum Outside AirStart-Up Evaporative Cooling optional Start-Up Water Wizard optional Operation - Water Wizard optional External Signal a variable Check Operation VAV Units optionalBuilding Pressure Control Damper actuator may take a few Check Operation Recirculating Units optionalRecirculation Operation Building Pressure Control aExhaust Fan Contact S1 Manually Closed optional Sequence of Operation Staged SequenceSequence of Operation 21 Modulation Sequence Operation Modulation Staged Controller Discharge Air Temperature dtSOutside Air Temperature OAt Sequence of Operation Modulation SequenceLight Off Blinking Sequence of Operation 41 Electronic ModulationProgram Revision Number Optional Room Override ROtSequence of Operation Electronic Modulation Staging Control Sequence of Operation Sequence of Operation Staged ControlFollowing are the green LED codes of operation Operation and Errors Ignition ControllerOption EC-2 Outside Air Enthalpy Reference Option EC-1 Outside Air Temperature ReferenceOption EC-3 Differential Temperature Control Operation EconomizerBlower Does Not Operate TroubleshootingMotor Over Amps Too Much Airflow Insufficient AirflowExcessive Noise or Vibration Improper manifold pressure Single or 21 Stage Furnace Will Not LightModulating Furnace Will Not Light Heat transformer TR2 fault Ignition controllers IC# failed Staged Furnace Will Not Light Internal high limit tripped temperature above set point Water Blows through Evaporative Cooler Evaporative Cooler does not Operate Recirculating pumpAdjust the Manual Supply Valve Adjust the On Time FactorWater Wizard Improper Water Supply Wheels Maintenance RoutineBelt Drives Snow AccumulationEvaporative Coolers MotorsFilters Chilled Water CoilsMaintenance Fall Flushing Coils Reference Model IGX Venting Connection Location Reference Model IG Venting Connection LocationReference Model IG Single or 2 Stage Reference Model IG Staged Reference Model IG Modulation Modulating Reference Model IGX Blower Control Center Manifold Gas Pressure Test Port Staged Inch Gas Supply Manifold Gas Pressure Test Port Modulating Staged Performance Table Reference Performance TableStart-Up Checklist Reference Start-Up ChecklistWarranty Maintenance Log