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WBII-SER Rev G Service Manual Models: 51 - 211 WARNING This manual must only be used by a qualified heating installer / service technician. Read all instructions, including this manual and the Knight Wall Mount Installation and Operation Manual, before installing.
Installer – Read all instructions, When calling or writing about the boiler WARNING NOTICE including this manual and the Knight – Please have the boiler model and serial Wall Mount Installation and Operation number from the boiler rating plate. Manual, before installing. Perform steps Consider piping and installation when in the order given.
Service Manual Please read before proceeding When servicing boiler – • To avoid electric shock, disconnect electrical supply before performing maintenance. • To avoid severe burns, allow boiler to cool before performing maintenance. Boiler operation – • Do not block flow of combustion or ventilation air to the boiler.
• Service and maintenance schedules • Address reported problems • Typical system components • Inspect boiler area and boiler interior The Knight wall mount boiler display • Clean condensate trap • Check all piping for leaks • Display panel readout, buttons and their functions •...
Near boiler piping This piping reference is included to specify the Near Boiler Piping specific to the Knight wall mount boiler. This piping scheme is important for proper operation of the SMART SYSTEM control. See the Knight Wall Mount Installation and Operation Manual for more detailed piping diagrams.
Service Manual Service Service (continued) The Knight wall mount display NAVIGATION DIAL The information on the bottom of the display shows the functions of the two SELECT keys (on either corner), and the NAVIGATION dial (in the center): MENU = Left SELECT Key...
Service Manual Service Service Control inputs SYSTEM PUMP SPEED CONTROL GAS PRESSURE SWITCH DHW THERMOSTAT ROOM THERMOSTAT / ZONE CONTROL LOW VOLTAGE CONNECTION FLOW SWITCH BOARD SYSTEM SENSOR OUTDOOR SENSOR BUILDING MANAGEMENT SYSTEM LOW WATER CUTOFF INLET TEMPERATURE SENSOR OUTLET TEMPERATURE / HIGH LIMIT SENSOR FLUE GAS SENSOR PRESSURE SWITCH...
Service Manual Service Service (continued) Control outputs ALARM BELL LOW VOLTAGE AUX. DEVICE RELAY CONNECTION BOARD RUN TIME CONTACTS BUILDING MANAGEMENT SYSTEM BOILER PUMP SYSTEM PUMP DHW PUMP IGNITOR BLOWER SMART CONTROL MODULE GAS VALVE DISPLAY PANEL PC INTERFACE...
How the boiler operates Access modes User The Knight wall mount boiler uses an advanced stainless steel heat exchanger and an electronic control module that allows The user can adjust space heating and tank target temperatures fully condensing operation. The blower pulls in gas and air by pressing the NAVIGATION dial when “SETPOINTS”...
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Service Manual Service Service (continued) 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).
Service Manual Service Service Sequence of operation (continued) OPERATION DISPLAY 8. If the space heating call for heat is active, and the tank thermostat or sensor starts a DHW call for heat, the boiler will switch to the DHW mode. If programmed for normal DHW operation (not as a zone), the DHW pump will turn on first, then the boiler pump will turn off (boiler and DHW pump operation briefly overlap to ensure flow is maintained through the unit).
Service Manual Service Service (continued) Display panel menu access Table 1-2 Use this procedure to access menus from the display panel SCREEN BUTTON OPERATION DISPLAY STATUS [SHDN] Press the RIGHT SELECT soft key [SHDN]. [YES] Press the LEFT SELECT soft key [YES]. Press and hold the LEFT SELECT soft key [MENU] [MENU] for five (5) seconds.
Service Manual Service Service Display panel parameter access Table 1-3 This is a typical example of accessing a parameter, shown for parameter Temperature Settings, MIN SH Setpt SCREEN BUTTON OPERATION DISPLAY STATUS This example shows how to access parameter Temperature Settings. The first display shown is at the beginning of the menu listings, after entering the installer access code.
Service Manual Service Service (continued) Parameter table Table 1-4 This table lists SMART SYSTEM control module parameters and where to access them User Access Installer Access Menu Description Page Display Modify Display Modify Time and Date Software Version (read only) Temperature Units (ºC/ºF) SH Night Setback Offset SH Night Setback On Times...
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Service Manual Service Service Parameter table Table 1-4 (continued from previous page) This table lists SMART SYSTEM control module parameters and where to access them User Access Installer Access Menu Description Page Display Modify Display Modify DHW Boiler Set Point Tank Set Point Tank Set Point Differential DHW Boiler Offset...
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Service Manual Service (continued) Parameter table Table 1-4 (continued from previous page) This table lists SMART SYSTEM control module parameters and where to access them User Access Installer Access Menu Description Page Display Modify Display Modify Boost Temperature Boost Time Anti-Cycling Time Anti-Cycling Override Differential Ramp Delay...
Service Manual Service Parameter table Table 1-4 (continued from previous page) This table lists SMART SYSTEM control module parameters and where to access them User Access Installer Access Menu Description Page Display Modify Display Modify BMS Type Volts at Min Volts at Max Rate at Min Volts Rate at Max Volts...
Service Manual Service (continued) Viewable and changeable control parameters Before changing parameters, note the Space Heating (SH) and Domestic Hot Water (DHW) CAUTION settings so that the unit can be returned to Night Setback On Times its original operating parameters. This is the time in which the SH Night Setback Offset becomes General active.
Service Manual Service To save any changes and return to the Home Screen, press 3-Way Valve Time the RIGHT SELECT [HOME] key. To return to the Status The optional Lochinvar Multi-Temperature Loop Control Screen without saving the changes, press the LEFT SELECT Board (MTLCB) can be used to control the supply temperature [EXIT] key.
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The default value is 125°F (52°C). DHW Type Tank Set Point Differential This parameter determines whether the Knight wall mount When a tank sensor is installed, the tank temperature must boiler treats the indirect DHW tank as a separate load, or as a drop this amount below the tank set point (DHW Tank zone on the primary loop.
Service Manual Service Service Outdoor Reset Set Point (1 - 3) at Low Outdoor Temperature When the outdoor air temperature drops to the Outdoor The option of controlling up to three (3) different outdoor (1 - 3) Low parameters, the calculated set point will be at resets for low outdoor temperatures is available.
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Service Manual Service (continued) Outdoor Air Shutdown Differential (SH1 - SH3) Boost Time The outdoor air shutdown differential parameter is the The boost time parameter sets the amount of time that must number of degrees below Outdoor Air Shutdown SH1, SH2, elapse with a SH demand before the water temperature calculated and SH3 parameters the outdoor air temperature must go set point will be increased.
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Service Manual Service Ramp Settings The set point or modulation of the boiler may be controlled Please note that the brackets ([]) denote NOTICE through the 0 - 10V BMS input or through ModBus. When the screen status. BMS parameter is set to INACTIVE, the 0 - 10V input will be The SMART SYSTEM control can be programmed to limit the ignored.
Service Manual Service Service (continued) The other Cascade divider method is Efficiency Minimum On/Off Time Optimization, designated as EFF in the menu. This In order to prevent units in a Cascade from short cycling, method is used, as the name implies, when it is desired this parameter defines the minimum ON and OFF time for to have the most efficient system.
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Service Manual Service Boiler Pump Delay DHW Blocks Sys Pump The SH pump delay parameter sets the length of time the When the indirect DHW tank is connected as a zone on the boiler pump will run after a SH demand has been satisfied. primary loop, the DHW Blocks Sys Pump parameter tells the Setting the delay time to 0 will disable the pump.
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Service Manual Service (continued) Set Point at Minimum Volts Service Notification Cycles When programmed for BMS control through the 0 - 10V BMS When the boiler control determines that a scheduled input or through ModBus and the BMS Type is programmed as service is due based on the number of boiler cycles, the SETPOINT, the set point represented by the Volts at Minimum boiler display will alternate the standard boiler display...
Maintenance Maintenance and annual startup Table 2-1 Service and Maintenance Schedules Owner maintenance Service technician (see the Knight Wall Mount User’s Information (see the following pages for instructions) Manual for instructions) General: • Address reported problems • Check boiler area •...
2. Verify that air intake area is free of any of the contaminants listed in Section 1 of the Knight Wall Mount Installation and Operation Manual. If any of these are present in the boiler intake air vicinity, they must be removed.
Tanks may be open, closed or diaphragm or bladder may result. If no water flows, valve is type. See Section 6 - Hydronic Piping of the Knight Wall inoperative. Shut down the boiler until a Mount Installation and Operation Manual for suggested new relief valve has been installed.
1. Start boiler and perform checks and tests specified 3. See Section 3 - Troubleshooting in this manual for other in Section 10 - Start-up of the Knight Wall Mount procedures to deal with low flame signal. Installation and Operation Manual.
Oiled bearing circulators the heat exchanger. 8. Finish cleaning using a clean cloth dampened with warm 1. The circulator shipped with the Knight wall mount boiler water. Rinse out debris with a low pressure water supply. is water-lubricated. No oiling is required.
(LP) with gas flowing (verify during boiler 8. Restore power to the boiler at the external line switch and verify startup) boiler operation (Section 10 - Start-up in the Knight Wall Mount Installation and Operation Manual) after completing boiler service.
Service Manual Troubleshooting Table 3-1 Troubleshooting Chart - No Display FAULT CAUSE CORRECTIVE ACTION - No 120 vac supplied to unit. • Check external line switch, fuse, or breaker. • Check position of ON/OFF switch. Turn switch to the ON position. •...
It is important to note that the flue and outlet water sensors have two temperature sensing devices in one housing. These devices are designated as S1a/S1b, outlet sensor and S3a/S3b, flue sensor. Please reference the wiring diagram in the Knight Wall Mount Installation and Operation Manual for correct terminal location.
Clean or replace the burner as necessary. - Low water flow through the heat exchanger. • Refer to Section 6 - Hydronic Piping of the Knight Wall Mount Boiler Installation and Operation Manual for minimum flow rates. Verify that the boiler is piped in a primary/secondary fashion and that the boiler and system pump are running on a call for heat.
Either the optional manual reset low gas Gas Pressure SW pressure switch or the optional manual reset • Refer to Section 7 - Gas Connections of the Knight (will require a manual high gas pressure switch tripped. Wall Mount Boiler Installation and Operation Manual reset once the condition for detailed information concerning the gas supply.
4 - 14 inches w.c. and LP gas pressures should be between 8 - 14 inches w.c. Refer to Section 7 - Gas Connections of the Knight Wall Mount Boiler Installation and Operation Manual for detailed information concerning the gas supply.
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• Replace high limit. • Adjust the set point of the manual reset limit to a higher setting up to a maximum of 210°F. Reference the Knight Wall Mount Installation and Operation Manual for Outlet MRHL adjusting procedures. (will require a manual •...
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• Replace high limit. • Vent/air intake lengths exceed the maximum allowed lengths. Refer to Section 3 - General Venting of the Knight Wall Mount Boiler Installation and Operation Fan Low/High Manual for proper lengths. • Check for obstruction or blockage in the vent/air...
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Service Manual Troubleshooting (continued) Table 3-4 (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface FAULT DESCRIPTION CORRECTIVE ACTION • Check the sensors and their associated wiring. Sensor Shorted Repair or replace the sensor or wiring if damaged. (will require a manual reset once the condition has been Either the inlet water or outlet water...
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Service Manual Troubleshooting Table 3-4 (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface FAULT DESCRIPTION CORRECTIVE ACTION • Check wiring to sensor. Make sure wiring is connected and not damaged. Reconnect / repair Flue Sensor Fault wiring if necessary.
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• Verify that the boiler pump is set to the proper speed or that the pump is the proper size. Reference Section 6 - Hydronic Piping of the Knight Wall Mount Boiler Installation and Operation Manual for boiler pump specifications.
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• Verify that the boiler pump is set to the proper speed or that the boiler pump is the proper size. Reference Outlet Temp Section 6 - Hydronic Piping of the Knight Wall Mount High Outlet water temperature has exceeded the...
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Service Manual Troubleshooting (continued) Table 3-4 (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Boiler Interface FAULT DESCRIPTION CORRECTIVE ACTION 120 vac input to the main control board has • Check 120 vac supply to the transformer. dropped below 80 vac.
Table 3-5 Troubleshooting Chart - Combustion Levels POSSIBLE CAUSE CORRECTIVE ACTION • Refer to Section 3 - General Venting of the Knight Wall Mount Installation and Operation Vent/Air Intake Length Manual for the proper venting and air intake methods for the Knight wall mount boiler.
Service Manual Troubleshooting (continued) Gas valve adjustment procedure If adjustment of the gas valve is deemed necessary, use the following procedures: Locate the throttle adjustment screw on the side of the venturi valve (FIG. 3-2). Using a screwdriver, turn the screw a 1/4 turn counterclockwise to increase CO levels or a 1/4 turn clockwise to decrease CO...
Revision Notes: Revision A (ECO #C05747) initial release. Reflects the new model numbers for the Knight Wall Mount upgrade. Revision B (ECO #C06234) reflects changes made to the Service Notification parameter. Revision C (ECO #C08372) reflects changes made to the parameter table, parameter descriptions, addition of the rope gasket, and updates to the troubleshooting chart.
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