Lochinvar 500, 90 service manual 6Combustion Air from Outside Single Opening

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1Determine boiler location

Installation & Service Manual

￿CAUTION

Under no circumstances should the room where the appliance is installed ever be under a negative pressure. Particular care should be taken where exhaust fans, attic fans, clothes dryers, compressors, air handling units, etc., may take away air from the appliance.

Figure 1-6_Combustion Air from Outside Single Opening

4.If a single combustion air opening is provided to bring combustion air in directly from the outdoors, the opening must be sized based on a minimum free area of one square inch per 3000 Btu/hr (7 cm2 per kW). This opening must be located within 12" (30 cm) of the top of the enclosure (see FIG. 1-6).

Combustion air requirements are based on the latest edition of the National Fuel Gas Code, ANSI Z223.1, in Canada refer to National Standard CAN B149.1. Check all local code requirements for combustion air.

All dimensions are based on net free area in square inches. Metal louvers or screens reduce the free area of a combustion air opening a minimum of approximately 25%. Check with louver manufacturers for exact net free area of louvers. Where two openings are provided, one must be within 12" (30 cm) of the ceiling and one must be within 12" (30 cm) of the floor of the room where the appliance is installed. Each opening must have a net free area as specified in Table 1B (on page 13). Single openings shall be located within 12" (30 cm) of the ceiling.

The combustion air supply must be completely free of any flammable vapors that may ignite or chemical fumes which may be corrosive to the appliance. Common corrosive chemical fumes which must be avoided are fluorocarbons and other halogenated compounds, most commonly present as refrigerants or solvents, such as freon, tricholorethylene, perchlorethylene, chlorine, etc. These chemicals, when burned, form acids which quickly attack the heat exchanger finned tubes, headers, flue collectors, and the vent system. The result is improper combustion and a non-warrantable, premature appliance failure.

The result is improper combustion and a non-warrantable, premature appliance failure.

EXHAUST FANS: Any fan or equipment which exhausts air from the equipment room may deplete the combustion air supply and/or cause a downdraft in the venting system. Spillage of flue products from the venting system into an occupied living space can cause a very hazardous condition that must be immediately corrected. If a fan is used to supply combustion air to the equipment room, the installer must make sure that it does not cause drafts which could lead to nuisance operational problems with the appliance.

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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 Venting Conventional Negative Draft Venting SystemVent Pipe Sizes Venting Vertical Vent Termination Clearances Less from Ridge From Parapet WallMasonry Chimney Installation Vent MaterialsSidewall Venting NumberAutomatic Vent Damper 7CB with Vent Damper and Vent Damper Terminal BlockGas connections Gas Supply Gas Pressure TestGas Connection Manifold PressureInstall Piping to Control Gas PipingGas Manifold Pressure Adjustment Procedure Clockwise to raise regulator gas pressure, counterclockwiseChecking Gas Supply Pressure 4Gas Supply PressureCombination Gas Valves Venting of Combination Gas ValvesTwo Stage Burner Control System Water Flow Switch if equipped Hydronic pipingRelief Valve Typical Heating Boiler Installations Low Water Cutoff if equippedMinimum Required Flow For Heating Boiler General Plumbing RulesSystem Temperature Rise Chart Piping of the Boiler SystemHeat Exchanger Pressure Drop Chart Circulator Pump SpecificationsWater Connections Heating Boilers Only 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 Terminal Strip Wiring Boiler Operating Temperature ControlPower Venter Connection to Terminal Strip Electrical connectionsTemperature Adjustment Pump Wiring for a Heating BoilerOperating Temperature Control Locating Temperature Control Temperature Control SettingsMaximum SET Point Determination Maximum Set Point DeterminationTemperature Control Sensors Inlet Water Temperature SensorMulti-Purpose Temperature Sensor Outdoor Air Temperature SensorOutdoor Air Reset Option Installation of a Remote Sensor Boiler ApplicationInstallation of a Tank Sensor Water Heater Application Additional Temperature Controls Blocked Vent and Flame Roll-Out / Flame Interlock Switch Manual Reset High Water Temperature Limit ControlPre-start Checklist Start-upInitial Start-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 Safety Shutoff Test for Spark Ignition Pilot System Intermittent Pilot Spark Ignition System F9/M9Freeze Protection To Turn Off Gas to ApplianceWater Treatment Freeze Protection for a Heating Boiler System if requiredRequired Temperature Rise Required Temperature RiseDomestic water heaters Domestic Water Heaters 90,000 500,000 Btu/hr ModelsWater Chemistry Softened Water SystemsPump Operation 1Single water heatersingle tank 2Single water heatermultiple tank 3Multiple water heatersingle tank Remote Sensor Installation Thermostat SettingsMinimum Pump Performance Heat Exchanger5Danger Warning Water Flow Switch if equipped Pressure Only Relief ValveThermal Expansion Cathodic ProtectionMaintenance and annual startup Service technicianOwner maintenance See the User’s Information Manual for instructionsMaintenance Check Expansion Tank Check Relief ValveCheck All Wiring Check Control SettingsCombustion Air Adjustment Perform Start-up and ChecksInspect and Clean Burner Heat Exchanger / Burner AccessInspection and Cleaning Procedure Pilot Flame Adjustment Procedure Clear AreaInspection of Heat Exchanger Waterways Water Circulating PumpReview with owner Gas Train and ControlsTroubleshooting Pilot or replace Diagrams Schematic Diagram F1 UnitWiring Diagram F1 Unit 90,000 270,000 Btu/hr ModelsSchematic Diagram F9 Unit Wiring Diagram F9 Unit315,000 399,999 Btu/hr Models Diagrams Diagrams Page Revision a ECO #C06290 initial release CFA-I-S Rev a 09/10
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