Lochinvar 500, 90 service manual Pilot or replace

Page 62

Installation & Service Manual

9Troubleshooting

Troubleshooting Guide:

90,000 - 270,000 Btu/hr Models - Water Heaters F1

Step 1:	Is the pilot lit?
Step 1:	Is the pilot lit?				No		Check gas pressure.
							Check the pilot assembly
							and thermocouple. Clean
							the thermocouple and
		Yes					the thermocouple and
		Yes					pilot or replace.

Check for an open sensor. If no open sensor, make sure there’s a call for heat. If call for heat is present, replace temperature control

Step 2:

Step 3:

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Is the gas valve getting 24VAC to the MV terminal?

Yes

Check gas pressure and make sure the gas valve knob is on

No

Check voltage to and from the transformer.

No

Check incoming 120 VAC

No		Is there 24 VAC (purple
		wire) on the 4-pin
		connector plug on the
		temperature controller?


			Yes

No

Check 24 VAC at R and W on the terminal strip.

Yes

Check each of the following for an open: -white and purple wire on the LWCO plug -rollout switch -manual reset high limit -spill switch

If any of these devices are open, press the reset button.

No

Is there 24 VAC (tan wire) on the 4-pin connector plug on the temperature controller?

Yes

Check each of the following for an open:

-X and B on the terminal strip -purple and gray wires on the vent damper plug

-V and P on the terminal strip -auto reset high limit

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Contents Models 90,000 500,000 Btu/hr Contents Please read before proceeding Checking equipmentCodes Ratings Copper-fin =B=R RatingCopper-fin Specifications Copper-fin How it works Gas connection pipeModels CWN270 Front View Model CWN399 Front View 422 Determine unit location Location of unitDetermine boiler location 3Combustion Air Direct from Outside6Combustion Air from Outside Single Opening Minimum Recommended Combustion AIR Supply to Equipment Room Vent Pipe Sizes VentingConventional Negative Draft Venting System Venting Vertical Vent Termination Clearances Less from Ridge From Parapet WallSidewall Venting Masonry Chimney InstallationVent Materials NumberAutomatic Vent Damper 7CB with Vent Damper and Vent Damper Terminal BlockGas Connection Gas connectionsGas Supply Gas Pressure Test Manifold PressureInstall Piping to Control Gas PipingGas Manifold Pressure Adjustment Procedure Clockwise to raise regulator gas pressure, counterclockwiseChecking Gas Supply Pressure 4Gas Supply PressureTwo Stage Burner Control System Combination Gas ValvesVenting of Combination Gas Valves Relief Valve Water Flow Switch if equippedHydronic piping Minimum Required Flow For Heating Boiler Typical Heating Boiler InstallationsLow Water Cutoff if equipped General Plumbing RulesSystem Temperature Rise Chart Piping of the Boiler SystemWater Connections Heating Boilers Only Heat Exchanger Pressure Drop ChartCirculator Pump Specifications Circulator Pump RequirementsPrimary/Secondary Boiler Piping Three Way Valves Boiler Flow RatesPrimary / Secondary Piping 4Primary / Secondary Piping of a Single BoilerNot to Exceed 4 Pipe DIA or MAX. of 12 Apart 8Multiple Boilers Zoned with Circulators Power Venter Connection to Terminal Strip Terminal Strip WiringBoiler Operating Temperature Control Electrical connectionsOperating Temperature Control Temperature AdjustmentPump Wiring for a Heating Boiler Maximum SET Point Determination Locating Temperature ControlTemperature Control Settings Maximum Set Point DeterminationMulti-Purpose Temperature Sensor Temperature Control SensorsInlet Water Temperature Sensor Outdoor Air Temperature SensorInstallation of a Tank Sensor Water Heater Application Outdoor Air Reset OptionInstallation of a Remote Sensor Boiler Application Additional Temperature Controls Blocked Vent and Flame Roll-Out / Flame Interlock Switch Manual Reset High Water Temperature Limit ControlInitial Start-up Pre-start ChecklistStart-up Lighting Instructions 1Gas Valve 90,000 270,000 Btu/hr ModelsSafety Shutoff Test For Standing Pilot Ignition System To Turn OFF GAS to ApplianceOperating Instructions Freeze Protection Safety Shutoff Test for Spark Ignition Pilot SystemIntermittent Pilot Spark Ignition System F9/M9 To Turn Off Gas to ApplianceWater Treatment Freeze Protection for a Heating Boiler System if requiredDomestic water heaters Required Temperature RiseRequired Temperature Rise Domestic Water Heaters 90,000 500,000 Btu/hr ModelsPump Operation Water ChemistrySoftened Water Systems 1Single water heatersingle tank 2Single water heatermultiple tank 3Multiple water heatersingle tank Minimum Pump Performance Remote Sensor InstallationThermostat Settings Heat Exchanger5Danger Warning Thermal Expansion Water Flow Switch if equippedPressure Only Relief Valve Cathodic ProtectionOwner maintenance Maintenance and annual startupService technician See the User’s Information Manual for instructionsMaintenance Check Expansion Tank Check Relief ValveCombustion Air Adjustment Check All WiringCheck Control Settings Perform Start-up and ChecksInspection and Cleaning Procedure Inspect and Clean BurnerHeat Exchanger / Burner Access Inspection of Heat Exchanger Waterways Pilot Flame Adjustment ProcedureClear Area Water Circulating PumpReview with owner Gas Train and ControlsTroubleshooting Pilot or replace Wiring Diagram F1 Unit DiagramsSchematic Diagram F1 Unit 90,000 270,000 Btu/hr Models315,000 399,999 Btu/hr Models Schematic Diagram F9 UnitWiring Diagram F9 Unit Diagrams Diagrams Page Revision a ECO #C06290 initial release CFA-I-S Rev a 09/10