Lochinvar 000 - 2, 495, 065 service manual Sequence of Operation, Ignition System Checkout

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Hydronic Heating Boilers and Domestic Water Heaters

CLEANING AND MAINTENANCE CONTINUED

A faulty hot surface igniter or ignition module must be replaced with an identical part. A specification igniter and ignition module for this specific unit is available from your local distributor. Do not use general purpose field

replacement ignition modules or igniters.

Ignition System Checkout

1.Turn off gas supply to unit.

2.Turn electric power on.

3.Adjust the set point on the temperature control to a setting above water temperature or to the highest safe setting.

4.The igniter will cycle on trial for ignition.

5.The ignition module will lock out and turn the alarm light on.

6.Adjust the Set Point Differential and High-Fire Offset to the desired settings.

7.Turn on gas supply.

8.Press the module reset button to reset the ignition module. This is a red button beside the ignition module or on the diagnostic panel on the header-end of the unit.

9.If ignition system fails to operate properly, repair work must be performed by a qualified service person or installer.

SEQUENCE OF OPERATION

OVERVIEW

This sequence of operation can be considered the order of events in sequential order that occur after the appliance has received a call for heat. The process begins with 120VAC power entering the appliance and ends with the appliance going into an idle state after completion of a successful call for heat.

Note: The following descriptions do not include remotely connected devices that may be connected to the appliance. Refer to the wiring diagram for actual point to point wiring connections that show power delivery.

1.The POWER switch is placed in the “ON” position.

2.120VAC power is supplied to the control transformer along with L1 and F1 on the ignition module.

3.24VAC is supplied to the electronic temperature control, the ignition module and the adjustable high limit control.

4.24VAC is then supplied to the auxiliary limit control (if equipped).

5.If equipped, 24VAC is supplied to a low water cut-off and then to the high and low gas pressure switches.

6.24VAC is supplied to the continuous alarm terminals A1 and A2 and then to the remote stage one terminal strip, 1C and 1NO.

7.24VAC is supplied to the electronic temperature control.

8.The electronic temperature control then calls for heat.

9.24VAC is supplied to the intermittent alarm field safety contacts, B1 and B2.

10.24VAC is supplied to the water flow switch (if equipped).

11.24VAC is supplied to the TH terminals on the ignition module.

12.As power is applied to the TH terminals on the ignition module, 120VAC is switched from the F2 terminal to start the combustion air fan at full speed on the 495,000 - 745,000 Btu/hr models and at low speed on the 985,000 - 2,065,000 Btu/hr models.

13.24VAC is supplied to the C terminal of the air pressure switch. As the low air switch makes, power is supplied to the ignition module.

14.24VAC is then supplied to the PS terminals on the ignition module as the air pressure switch makes to prove fan operation..

15.The combustion air fan operates for the pre-purge period.

16.At the end of the pre-purge, 120VAC is applied to the hot surface igniter and the trial for ignition light.

17.The hot surface igniter proves 1800 F (982 C) ignition temperature by current draw through the ignition module.

18.The ignition module supplies voltage to the MV terminals on to the gas valve(s).

F9 SINGLE STAGE FIRING

19.All gas valves on the 495,000 - 745,000 Btu/hr models and approximately half of the valves on the 985,000 - 2,065,000 Btu/hr models open, supplying gas to the orifice and burner inlet to pre-mix.

20.The gas/air mixture is forced into the burner and out of the burner ports under pressure.

21.The hot surface igniter lights the gas/air mixture and then serves as a flame sensor to prove main burner flame by rectification.

22.After a time delay of 10 seconds, the remaining gas valves on the 985,000 - 2,065,000 Btu/hr models open, supplying gas to the remaining burners.

23.The gas/air mixture is forced out of the burners and out of the burner ports under pressure.

24.The burners light by carryover from the burners currently firing.

25.The heater is now firing at full rated input.

M9 MODULE FIRING

26.The first stage gas valve(s) opens and supplies gas to the orifice and burner inlet to pre-mix.

27.The gas/air mixture is forced into the burner and out of the burner ports under pressure.

28.The hot surface igniter lights the gas/air mixture and then serves as a flame sensor to prove main burner flame by rectification.

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Contents Domestic Water Heaters Save this manual for future referenceHydronic Heating Boilers and Domestic Water Heaters Safety Information General Product InformationHydronic Heating Boilers and Domestic Water Heaters Product Identification Front and Rear ViewBase for Combustible Floors InstallationClearances from Combustible Construction Outdoor Boiler Installation Hydronic System AntifreezeShut-Down and Draining Pump OperationCombustion Air Filter Installing Combustion Air FilterFreeze Protection for a Heating Boiler System if required Combustion Air Options One OpeningInstallation Venting General InformationExhaust Fans Venting SupportTABLE-A Vent System Options Table BFlue Pipe Sizes TABLE-CConventional Negative Draft Venting Negative DraftFlue Outlet Piping Common Venting SystemsOutdoor Installation Venting Masonry Chimney InstallationsTable D Outdoor Vent KitsOutdoor Vent/Air Inlet Location Outdoor Vent KitInput Max Min Gas Pressure TestGas Piping Connecting Gas Piping to Unit Gas Train and ControlsVenting of Combination Gas Valves Combination Gas ValvesChecking Gas Supply Pressure Gas Manifold Pressure Adjustment Measuring Gas Supply Pressure at Combination Gas ValveNET Manifold Pressure Regulator Pressure Less Front Chamber PressureWater Flow Switch Low Water CutoffRelief Valve If EquippedNominal AMP Draw Data Terminal Strip Connection OptionsTable J Water Connections Heating Boilers Only General Plumbing RulesPrimary/Secondary Boiler Piping Input LTV Valve Kit Btu/hr Low Temperature Return Water SystemsRadiant Floor and Snow Melt Heating Systems Installation with a Chilled Water System System Temperature Rise Chart Based on Btu/hr InputTable L 10ºF 20ºF 30ºF 40ºF 50ºF 60ºFTemperature/Pressure Gauge Boiler Flow RateBoiler Bypass Requirements Filling the SystemOperation Lighting InstructionsLocating Temperature Control To Turn Off Gas To ApplianceTemperature Control Settings Table MSet Point Maximum Set Point DeterminationOutdoor Air Reset Option High-Fire OffsetShutdown Outdoor Air Max O.A. MaxTemperature Control Sensors Placement of SensorsBoiler Application Water Heater ApplicationRemote Wire Connection Wire Maximum GaugeHot Surface Igniter and Ignition Control Module Table NDiagnostic Status Indication Hot Surface Ignition Control ModuleIgnition and Control Timings Ignition Module Lockout FunctionsTable P Status LED Diagnostic CodesTable O Required Temperature Rise Temperature Rise ChartDomestic Water Heaters Water Velocity ControlPipe Sizing Chart Water ChemistryCirculating Pump Table RPotable Hot Water Temperature Control Settings Domestic Water TemperaturesDomestic Water Minimum Pump PerformanceHigh Water Temperature Limit Control Location of Cold Water Supply Piping ConnectionsOptional Relief Valve Thermal ExpansionCleaning Maintenance Flue Gas Passageways Cleaning ProceduresCombustion and Ventilation Air Heat Exchanger CleaningElectrical Adjustment Procedure 495,000 1,255,000 Btu/hr Models Cleaning and MaintenanceSet Up Procedure Servicing Hot Surface Igniter and Ignition Module Sequence of Operation Ignition System CheckoutPower Supply ON/OFF Rocker SwitchManual Reset High-Limit Thermostat Safety Device TerminalsHeat Transfer Process Gas Valves, Burner Electronic Temperature ControllerIgnition Module Schematic Diagram BTU/HRHI-LIMITS PWR SW Main Unit GAS Valves Blower Pressure Switch Wiring Diagram 15AMPSControl BOX Connections Control BOX Connections

000 - 2, 065, 495 specifications

Lochinvar 000 - 2,495,065 is a cutting-edge water heating solution designed to meet the needs of modern residential and commercial applications. This high-efficiency unit combines advanced engineering with robust technologies, providing unmatched performance and reliability.

One of the standout features of the Lochinvar 000 - 2,495,065 is its high thermal efficiency, which often exceeds 95%. Utilizing condensing technology, the unit harnesses heat from exhaust gases, allowing it to recover otherwise lost energy, thereby reducing operational costs significantly. This efficiency not only lowers energy bills for users but also lessens the environmental impact by minimizing greenhouse gas emissions.

The Lochinvar 000 - 2,495,065 is equipped with a lightweight stainless steel heat exchanger. This construction ensures exceptional corrosion resistance and longevity, extending the lifespan of the unit while maintaining optimal performance. The stainless steel design also contributes to faster heating times, making it ideal for high-demand environments.

In terms of control technologies, the Lochinvar 000 - 2,495,065 features an intuitive touchscreen interface. This user-friendly design allows for seamless operation, real-time monitoring, and easy adjustments to temperature settings. Additionally, it facilitates remote diagnostics, promoting efficient maintenance and reducing downtime, which is crucial for busy facilities.

For enhanced safety, the Lochinvar 000 - 2,495,065 includes multiple safety mechanisms, such as over-temperature protection, flame safeguard, and leak detection systems. These safety features ensure secure operation and give users peace of mind.

Moreover, the unit is compatible with various fuel sources, including natural gas and propane, making it versatile and adaptable to different infrastructure requirements. This flexibility ensures that the Lochinvar 000 - 2,495,065 can be integrated into various settings, from residential homes to large commercial buildings.

Another significant characteristic is its compact design, allowing for easy installation in tight spaces. The footprint of the Lochinvar 000 - 2,495,065 makes it an ideal solution for applications where space is at a premium, without compromising on performance.

In summary, Lochinvar 000 - 2,495,065 represents a premium choice for water heating solutions, merging advanced technologies, high efficiency, and user-friendly design to cater to a wide range of heating needs while ensuring safety and sustainability.
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