Lochinvar 1, 000 through 2 warranty Relief Valve, Diaphragm GAS Valve Ratio GAS Valve

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RELIEF VALVE

This unit is supplied with a relief valve(s) sized in accordance with ASME Boiler and Pressure Vessel Code, Section IV (“Heating Boilers”). The relief valve(s) is installed in the vertical position and mounted in the hot water outlet. No valve is to be placed between the relief valve, and the unit. To prevent water damage, the discharge from the relief valve shall be piped to a suitable floor drain for disposal when relief occurs. No reducing couplings or other restrictions shall be installed in the discharge line. The discharge line shall allow complete drainage of the valve and line. Relief valves should be manually operated at least once a year.

CAUTION￿

Avoid contact with hot discharge water.

NOTE:

The gas train and controls assembly provided on this unit have been tested under the applicable American National Standard to meet minimum safety and performance criteria such as safe lighting, combustion and safety shutdown operation.

air blower. The valve is a 1:1 differential pressure air/gas ratio controller. The valve adjusts the same pressure difference on the gas side as it senses on the air side. The valve performs the functions of safety shutoff, constant pressure regulation and air/gas ratio control. Slow opening and safety shutoff is accomplished by operation of an electro hydraulic cylinder. Full closing of the valve seat occurs in less than 0.8 seconds when the valve is de-energized. A visual stroke position indicator is provided on the valve assembly to indicate the position of the valve seat. Operation of the gas valve in combination with the combustion air blower allows the burner input rate to vary from 25% to 100% based on temperature demand. There is no need for an additional upstream constant gas pressure regulator internally to the appliance as long as the gas supply is maintained within the specified minimum and maximum pressures.

The manifold pressure is preset at the factory and adjustment is not usually required if gas supply pressure is maintained within the specified range. If the manifold pressure is to be measured, follow the “Gas Manifold Pressure Measurement Procedure” for proper measurement.

There are no serviceable parts on the ratio gas valve actuator.

DIAPHRAGM GAS VALVE

RATIO GAS VALVE

FIG. 43 Ratio Gas Valve

The main gas valve supplying gas to the burner on this appliance utilizes a pressure regulating electro hydraulic actuator providing a slow opening, fast closing safety shut off and air/gas ratio control for the gas combustion process. This gas valve controls the pressure difference across the restriction in the gas supply line as a function of the pressure difference across the combustion air supply to the burner. The actuator maintains a constant air to gas ratio as the volume of air changes based on the operation of the combustion

FIG. 44 Diaphragm Gas Valve

A diaphragm type gas valve is also provided in the gas train. As the second valve seat in the gas train, it supplies a redundant safety shutoff valve seat in the gas supply to the burner to ensure safe operation in the remote event of a gas valve failure. The diaphragm gas valve is energized with 24 VAC power at the same time the ratio gas valve is powered in the operational sequence to ignite the burner.

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Contents
Warranty Special Instructions To OwnerIFB/IFW-i&s-05 Table of Contents Do not Checking EquipmentWhat to do if YOU Smell GAS Owner WarningRecommended Service Clearances Installation Procedure Location of UnitTable a Clearances from Combustible ConstructionCombustion Air Direct from Outside Minimum Recommended Combustion Table BAIR Supply to Mechanical Room 500 in2 3226 cm2 667 in2 4303 cm2 000 in2 12,903 cm2Construction Air Filter Construction AIR FilterVenting Construction AIR Filter Kits Table CTable D Category IV Flue Pipe SizesCategory IV Venting Category IV Positive Pressure Venting SystemCategory IV Flue Pipe Materials Venting Guidelines for a Category IV VentDrain Tee Installation General Category IV Vent Termination ClearancesExceed a maximum of 100 equivalent feet 30.5 m in length Vertical Venting Terminations Masonry Chimney InstallationsTable E Sidewall Venting TerminationsSidewall Vent Cap Kits Sidewall VentDirect Vent INTELLI-VENT Systems Location of a Sidewall Vent TerminationDirect Vent and Intelli-Vent Flue Air Inlet Pipe Sizes Table FAir Inlet Length of Air Inlet PipeCombined Combustion Air Inlet Points Vertical Direct Vent SystemsHorizontal Direct Vent Multiple Vertical Direct Vent InstallationsSidewall Combustion AIR Inlet Table GLocation of a Sidewall Air Inlet Cap These are Multiple Horizontal Direct Vent InstallationsCombined Air Inlet Points Table HMaximum Length of an Intelli-Vent System Air Inlet Sidewall Input Flue Pipe Btu/hr SizeAir Inlet Sidewall Input Flue Pipe Horizontal INTELLI-VENT with Vertical Combustion AIRBtu/hr Size Cap Kit 500,000 SVK3026Location of a Rooftop Air Inlet Cap Vertical Combustion Horizontal INTELLI-VENT AIR InletTable J Table K GAS Supply GAS Pressure TestGAS Connection Table LMultiple Appliance Installations Gas Pipe Size Chart Recommended Gas Pipe Size Single Appliance InstallationsTable M Table NInstall Piping to Control GAS Manifold Pressure AdjustmentGAS Piping Checking GAS Supply PressureChecking Manifold GAS Pressure Water Connections Water ConnectionsSecondary Heat Exchanger Primary Heat Exchanger Inlet and Outlet ConnectionsMinimum Pipe Size Requirements Bypass Valve Synchronization Integral BypassIntegral Circulator Bypass Piping AssemblyOptional Intermittent Pump Operation Bypass Initial Set-up of Maximum Water FlowBtu/hr Input Temperature Rise Minimum Water TemperaturesTable P Bypass OperationTable Q Water Flow SwitchLOW Water Cutoff GAS Train and ControlsDiaphragm GAS Valve Ratio GAS Valve Relief ValveElectrical Connections Jacket AssemblyFront Control Panel Locations Access to Components and ControlsTransformer and Relay Locations Variable Frequency DriveHigh GAS Pressure Switch LOW GAS Pressure Switch Optional LOW AIR Pressure SwitchExcel Be used as a diagnostic indicator Default Values Pre-programmed in the Excel Temperature AdjustmentTable S To Activate the Manual OverrideConfiguring Command Display Password FunctionTable T Display Default Values Accessing the SIX Changeable Points from Command DisplayTotal Run Time Calculated Set PointSet Point Temp Sequencing TypeCommand Display Data Screen Table U Status PointsStatus Point Operational Modes Hot Surface Igniter OnOptional on Heating Boilers Only Outdoor Reset Function SelectionsEfficiency Optimized with Time Equalization Multiple Appliance InstallationsSingly Terminated FTT Network Bus Topology Specifications Interfacing Multiple AppliancesTable W Additional Components Used to Interface Multiple Appliances Wire Termination for E-Bus ConnectionTypical Building Management System Diagram High Water Temperature Limit ControlService Parts HOT Surface Ignition SystemIgnition Module Lockout Functions Table Y Diagnostic Status IndicationIgnition and Control Timings Table ZIndicator OPERATION/DIAGNOSTIC LIGHTS, Resets and SwitchesBurner Table AACombustion Air Blower and Transition Chamber Combustion AIR BlowerSystem Optional Condensate ManagementTable BB Condensate Drain Location On RearCondensate Testing Condensate Trap InstallationReplenishing the Neutralizer Lighting Instructions Install Condensate TrapIgnition System Checkout To Turn OFF GAS to ApplianceHeat Transfer Process Sequence of OperationEnd of Sequence MaintenanceBurner Maintenance Burner Removal and CleaningLocation of Primary Heat Exchanger Burner Cleaning ProcedureSecondary Heat Exchanger Inspection Lubrication Freeze Protection Freeze Protection for a Heating Boiler System If Required Heating Boiler InstallationsWater Treatment Water Connections Heating Boilers onlyPiping Lengths Primary Loop Circulator Pump SpecificationsBoiler Circulator Pump Limitations Circulator Pump OperationPRIMARY/SECONDARY Boiler Piping Minimum Boiler Water TemperaturesTable CC Boiler Temperature Rise Chart Table DDMaximum Flow for Heating Boiler Btu/hr Input Maximum FlowTEMPERATURE/PRESSURE Gauge Typical Heating Boiler InstallationsPlacing the Boiler Operation Installation with a Chilled Water System Boiler Operating Temperature ControlBoiler Operation Typical Water Heater Piping with Storage Tank Water Velocity ControlTable EE Table FFMaximum Flow Rate Btu/hr Input Water Chemistry Single Water Heater Piping with Two Storage Tanks Piping Multiple Unit InstallationsPump Operation Table GGHeat Exchanger Common ManifoldTable HH Thermostat SettingsOptional Relief Valve Thermal ExpansionCathodic Protection Ladder Diagram PWM Wiring Diagram
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