Lochinvar WH 55-399 operation manual Sequence of operation, Operation Display

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Installation & Operation Manual

11 Operating information

Sequence of operation

OPERATION

DISPLAY

1.Upon a call for heat, the gas pressure switch(es) must be closed.

2.Once the gas pressure switch(es) are closed, the control turns on the appropriate pumps (system and boiler pumps for space heating, DHW pump for DHW). The flow switch and/or LWCO must close.

3.The control turns on power to the louver relay. The louver proving switch, air pressure switch, and blocked drain switch must close.

4.The control starts the prepurge cycle by initiating the blower.

5.The control starts the trial for ignition by firing the spark electrode and opening the gas valve.

6.If flame is not detected after the sparking ends, the control will perform a postpurge, then start another prepurge cycle and try to light the burner again. The control will perform a total of 4 attempts before locking out.

7.If flame is detected, it holds the firing rate steady for a few seconds to let the flame stabilize, then it begins to modulate the firing rate based on a set point or some other command (such as a 0-10V BMS signal).

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Contents Models WH 55 Contents When servicing boiler Please read before proceedingBoiler operation Boiler waterKnight Wall Mount Boiler How it works Stainless steel heat exchangerModels 55 Ratings Knight Wall Mount Boiler Ahri RatingInstallation must comply with Closet and alcove installationsDetermine boiler location Before locating the boiler, check1Closet Installation Minimum Required Clearances Precautions Vent and air pipingWall mounting location Prevent combustion air contaminationAreas likely to have contaminants When using an existing vent system to install a new boilerProducts to avoid When removing a boiler from existing common vent system Gas conversions Prepare boilerRemove boiler from wood pallet Mounting the boiler Mounting to a wood studded wallMounting to a concrete wall Mounting to a metal studded wallGeneral venting Direct venting options Sidewall VentInstall vent and combustion air piping Air intake/vent connectionsRequirements for installation in Canada SizingModel Kit Number Equivalent Vent Length Model Max Vent AirMaterials Air inlet pipe materialsOptional room air Air contaminationApproved PVC/CPVC Vent Pipe and Fittings Material StandardVent pipe Vent fittingsCentrotherm InnoFlue SW Duravent Polypro ModelPolypropylene Stainless steel vent If using the alternate sidewall termination Sidewall direct ventingVent/air termination sidewall Determine location2AClearance to Gravity Air Inlets Model Air Vent Centerline Width Prepare wall penetrationsPrepare wall penetrations Alternate Field Supplied Option Multiple vent/air terminationsDescription and usage Sidewall termination installationSidewall termination optional concentric vent 92 and 3 Concentric Vent Dimensional Drawing reference D on Sidewall termination optional concentric vent models12Concentric Vent Sidewall Attachment Multiventing sidewall terminationsPrepare roof penetrations Vertical direct ventingVent/air termination vertical Vertical termination installation Vertical termination optional concentric ventMultiventing vertical terminations Minimum Combustion AIR TypicalAlternate vertical concentric venting Vent / Air Inlet Size Minimum Existing Vent / Chase SizeConcentric Venting Arrangement Existing vent as a chaseHydronic piping System water piping methods General piping informationLow water cutoff device Chilled water systemNear boiler piping components Near boiler piping connections Circulator sizing20F Temperature Rise Applications 25F Temperature Rise Applications35F Temperature Rise Applications Pump Size GrundfosVariable speed pump option Smart System / Multi-temperature loop control optionVariable speed pump setup 3Single Boiler Primary / Secondary Piping Make UP Water Indirect Number of Units Boiler Member 8Single Boiler Multiple Temperature DHW Priority Model Required Pipe Sizes Boiler Make UP Boiler Connecting gas supply piping Gas connectionsNatural gas Propane GasLength of Pipe in Straight Feet for 1/2 PSI Natural Gas Pipe Capacity ChartCheck inlet gas supply Gas valve replacement Gas PressureLine voltage connections Field wiringInstallation must comply with Low voltage connections Outdoor temperature sensor Louver proving switchFlow switch ThermostatAlarm contacts Wiring of the cascadeSystem supply sensor Boiler management systemInstallation FieldwiringCondensate disposal Condensate drainFreeze protection when used Start-upCheck/control water chemistry Fill and test water systemClean/Inspect Trap Assembly Check for gas leaks Inspect/fill condensate systemCheck thermostat circuits Inspect/check condensate lines and fittingsFinal checks before starting the boiler Start the boilerIf boiler does not start correctly Check system and boiler2Operating Instructions Models 55 Operating Instructions Model Set space heating operation Natural Gas PropaneSet domestic hot water DHW operation Verify DHW modeConfiguration of the cascade Operating information General Protection features Boiler temperature regulation Outdoor reset operation, if used CascadeSequence of operation Operation DisplayUser Access modesInstaller Knight wall mount boiler control module 1Control PanelCall for Heat Information Dial Function Maintenance Maintenance and annual startup Service technicianOwner maintenance See the following pages for instructions GeneralMaintenance Check ignition ground wiring Check all boiler wiringCheck control settings Flue vent system and air pipingCheck flame signal Cleaning boiler heat exchangerPerform start-up and checks Check burner flameDiagrams PC Interface2Wiring Diagram