SWH-I-S Rev D TM Installation & Service Manual Models: SNR150-100, SNR200-100, SNA285-125, SNA400-125, AND SNA500-125 WARNING: If the information in these instructions is not followed exactly, a fire or explosion may result causing property damage, personal injury or death. -- Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance. -- WHAT TO DO IF YOU SMELL GAS • Do not try to light any appliance.
Contents PLEASE READ BEFORE PROCEEDING . . . . . . . . . . . 3 Hazard Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 THE SHIELD -- HOW IT WORKS . . . . . . . . . . . . . . . . . 4-6 RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1. DETERMINE WATER HEATER LOCATION Closet and Alcove Installations . . . . . . . . . . . . . . . . . . . . 8 Provide Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Flooring and Foundation . . . . . . . .
TM Installation & Service Manual Please read before proceeding Hazard definitions The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels or to important information concerning the life of the product. DANGER DANGER indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury.
TM Installation & Service Manual The Shield - How it works... 1. Access cover - front Provides access to the gas train and heat exchanger. 2. 3. Air intake adapter 19. Heat exchanger outlet temperature sensor Air pressure switch 20. High limit sensor Air shroud (500-125 Model Only_Not Shown) The air shroud directs air and gas flow into the blower. 5. Blower The blower pulls in air and gas through the venturi (item 5).
TM The Shield - How it works...
TM Installation & Service Manual The Shield - How it works...
TM Installation & Service Manual Ratings Model Number CSA Input Modulation Btu/hr Note: Change “N” to “L” for L.P. gas models.
TM 1 Determine water heater location Installation must comply with: WARNING • Local, state, provincial, and national codes, laws, regulations, and ordinances. • National Fuel Gas Code, ANSI Z223.1 – latest edition. • National Electrical Code. • For Canada only: B149.1 Installation Code, CSA C22.1 Canadian Electrical Code Part 1 and any local codes. NOTICE The Shield water heater gas manifold and controls met safe lighting and other performance under tests specified in ANSI Z21.10.3 – latest edition.
Installation & Service Manual TM 1 Determine water heater location (continued) Figure 1-1 Closet Installation - Minimum Required Clearances 1" MINIMUM CLEARANCE AROUND HOT WATER PIPES AND VENT PIPE WARNING 6" For closet installations, CPVC material MUST BE used in a closet structure due to elevated temperatures. Failure to follow this warning could result in fire, personal injury, or death.
TM 1 Installation & Service Manual Determine water heater location Flooring and foundation Table 1A Corrosive Contaminants and Sources Flooring Products to avoid: The Shield water heater is approved for installation on combustible flooring, but must never be installed on carpeting. Spray cans containing chloro/fluorocarbons WARNING Do not install the water heater on carpeting even if foundation is used. Fire can result, causing severe personal injury, death, or substantial property damage.
TM 1 Determine water heater location When removing a water heater from existing common vent system: DANGER Do not install the Shield water heater into a common vent with any other appliance. This will cause flue gas spillage or appliance malfunction, resulting in possible severe personal injury, death, or substantial property damage. Failure to follow all instructions can result in flue gas spillage and carbon monoxide emissions, causing severe personal injury or death.
TM 1 Installation & Service Manual Determine water heater location 2. If combustion and ventilation air is taken from the outdoors using a duct to deliver the air to the equipment room, each of the two openings should be sized based on a minimum free area of one square inch per 2000 Btu/hr (11 cm2 per kW) of input (see FIG. 1-4). Figure 1-3_Combustion Air Direct from Outside 1.
Installation & Service Manual TM 1 Determine water heater location (continued) TABLE - 1B MINIMUM RECOMMENDED COMBUSTION AIR SUPPLY TO EQUIPMENT ROOM FIG. 1-3 Model Number SNR150-100 SNR200-100 SNA285-125 SNA400-125 SNA500-125 FIG. 1-4 FIG. 1-5 FIG.
TM 2 Installation & Service Manual General venting Direct venting options Figure 2-1 Vertical Direct Venting (Two-Pipe Vertical Termination) - See page 25 for more details Figure 2-2 Sidewall Direct Venting (Two-Pipe Sidewall Termination) - See page 18 for more details Figure 2-3 Concentric Vertical Termination - See page 27 for more details Figure 2-4 Concentric Sidewall Termination - See page 22 for more details 14
TM 2 General venting Installation & Service Manual (continued) Venting and combustion air The Shield water heater must be vented and supplied with combustion and ventilation air as described in this section. Ensure the vent and air piping and the combustion air supply comply with these instructions regarding vent system, air system, and combustion air quality. See also Section 1 of this manual. DANGER NOTICE WARNING This appliance requires a special venting system.
TM 2 General venting Air intake/vent connections 1. 2. Installation & Service Manual Combustion Air Intake Connector (FIG.’s 2-5 and 2-6) - Used to provide combustion air directly to the unit from outdoors. A fitting is provided on the unit for final connection. Combustion air piping must be supported per guidelines listed in the National Mechanical Code, Section 305, Table 305.4 or as local codes dictate.
TM 2 General venting Installation & Service Manual (continued) Minimum / Maximum allowable Vent, air piping and termination: combustion air and vent piping lengths are The Shield water heater vent and air piping can be installed as follows: through the roof or through a sidewall. Follow the procedures in this manual for the method chosen. Refer to the information Vent = 12 equivalent feet minimum / 100 equivalent feet in this manual to determine acceptable vent and air piping maximum length.
Installation & Service Manual TM 3 Sidewall direct venting Vent/air termination – sidewall WARNING Follow instructions below when determining vent location to avoid possibility of severe personal injury, death, or substantial property damage. WARNING A gas vent extending through an exterior wall shall not terminate adjacent to a wall or below building extensions such as eaves, parapets, balconies, or decks.
TM 3 Sidewall direct venting Installation & Service Manual (continued) Vent/air termination – sidewall Figure 3-1C Alternate Venting Arrangement (if Space Allows) w/Field Supplied Fittings TO BOILER INTAKE AIR CONNECTION Figure 3-2B Alternate Clearance to Gravity Air Inlets w/Field Supplied Fittings COUPLING 12” MIN 15” MAX FROM BOILER VENT PIPE CONNECTION BIRD SCREEN 12” MIN BIRD SCREEN ALTERNATE VENTING ARRANGEMENT (IF SPACE PERMITS) 5. Maintain clearances as shown in FIG.
TM 3 Sidewall direct venting Prepare wall penetrations 1. 2. 3. 4. 5. Installation & Service Manual Use the factory supplied wall plate as a template to locate the vent and air intake holes and mounting holes. Air pipe penetration: a. Cut a hole for the air pipe. Size the air pipe hole as close as desired to the air pipe outside diameter. Vent pipe penetration: a. Cut a hole for the vent pipe.
TM 3 Sidewall direct venting Installation & Service Manual (continued) Vent/air termination – sidewall Figure 3-5A Multiple Vent Terminations (must also comply with Figure 3-1A) Figure 3-5B Alternate Multiple Vent Terminations w/Field Supplied Fittings (must also comply with Figure 3-1B) 12" MIN. BETWEEN EDGE OF AIR INLET AND ADJACENT VENT OUTLET VENT AIR VENT / AIR TERMINATION Multiple vent/air terminations 1.
Installation & Service Manual TM 3 Sidewall direct venting Sidewall termination – optional concentric vent Description and usage Lochinvar offers optional concentric combustion air and vent pipe termination kits (Factory Kit #CVK3003 for 3" diameter Models SNR150-100 - SNR200-100 and #CVK3007 for 4" diameter - Models SNA285-125 - SNA500-125). Both combustion air and vent pipes must attach to the termination kit.
Installation & Service Manual TM 3 Sidewall direct venting (continued) Sidewall termination – optional concentric vent Figure 3-9 Concentric Vent Dimensional Drawing Models SNR150-100 -- SNR200-100 / CVK3003 Figure 3-10 Concentric Vent Dimensional Drawing Models SNA285-125 -- SNA500-125 / CVK3007 "A" "C" DIA. "B" DIA. "D" 3" (76 MM) "E" "G" "H" DIA. "B" DIA.
TM 3 Installation & Service Manual Sidewall direct venting Sidewall termination – optional concentric vent Figure 3-12 Concentric Vent Sidewall Attachment Note: CVK3003 shown for illustration purposes. CAUTION DO NOT use field-supplied couplings to extend pipes. Airflow restriction will occur and may cause intermittent operation. 9. Cement appliance combustion air and vent pipes to the concentric vent termination assembly. See FIG. 3-12 for proper pipe attachment. 10.
TM 4 Installation & Service Manual Vertical direct venting Vent/air termination – vertical WARNING Follow instructions below when determining vent location to avoid possibility of severe personal injury, death or substantial property damage. WARNING Do not connect any other appliance to the vent pipe or multiple water heaters to a common vent pipe. Failure to comply could result in severe personal injury, death, or substantial property damage.
TM 4 Installation & Service Manual Vertical direct venting Vent/air termination – vertical Prepare roof penetrations Multiple vent/air terminations 1. Air pipe penetration: a. Cut a hole for the air pipe. Size the air pipe hole as close as desired to the air pipe outside diameter. 1. When terminating multiple Shield water heaters, terminate each vent/air connection as described in this manual (FIG. 4-2). 2. Vent pipe penetration: a. Cut a hole for the vent pipe.
TM 4 Vertical direct venting Installation & Service Manual (continued) Vertical termination – optional concentric vent Description and usage Lochinvar offers an optional concentric combustion air and vent pipe termination kit. Both combustion air and vent pipes must attach to the termination kit. The termination kit must terminate outside the structure and must be installed as shown in FIG. 4-4. Field supplied pipe and fittings are required to complete the installation. 3.
TM 4 Installation & Service Manual Vertical direct venting Vertical termination – optional concentric vent WARNING Do not operate the appliance with the rain cap removed or recirculation of combustion products may occur. Water may also collect inside the larger combustion air pipe and flow to the burner enclosure. Failure to follow this warning could result in product damage or improper operation, personal injury, or death. 5.
TM 5 Installation & Service Manual Conventional and sidewall venting The Shield water heater may be installed with a single pipe carrying the flue products to the outside while using combustion air from the equipment room. The vent pipe may terminate either vertically (FIG. 5-1) above the roof line in a conventional vent manner or on a sidewall (FIG. 5-2).
TM 6 Installation & Service Manual System piping System water piping methods 2. If this water heater is installed in a closed water supply system, such as the one having a backflow preventer in the cold water supply, provisions must be made to control thermal expansion. DO NOT operate this water heater in a closed system without provisions for controlling thermal expansion. Warranties do not cover damages from thermal expansion such as pressure bulges and/or deformities.
TM 6 System piping (continued) The following chart (Table 6A) details the relationship of water temperature and time with regard to scald injury and may be used as a guide in determining the safest water temperature for your applications.
TM 6 Installation & Service Manual System piping Figure 6-2 Single Unit COLD WATER SUPPLY FLOW CHECK VALVE (TYPICAL) EXPANSION TANK BUILDING RETURN SYSTEM CIRCULATOR MIXING VALVE HOT WATER SUPPLY BALL VALVE (TYPICAL) UNION (TYPICAL) 32
TM 6 System piping Installation & Service Manual (continued) Figure 6-3 Multiple Units COLD WATER SUPPLY FLOW CHECK VALVE (TYPICAL) UNION (TYPICAL) EXPANSION TANK BUILDING RETURN SYSTEM CIRCULATOR BALL VALVE (TYPICAL) MIXING VALVE HOT WATER SUPPLY 33
TM 6 Installation & Service Manual System piping Figure 6-4 Two Temperature - Single Unit THERMOMETER (TYPICAL) 180° HOT WATER SUPPLY FLOW CHECK VALVE (TYPICAL) BALL VALVE (TYPICAL) 140° HOT WATER SUPPLY MIXING VALVE LOW TEMPERATURE BUILDING RETURN COLD WATER SUPPLY EXPANSION TANK UNION (TYPICAL) HIGH TEMPERATURE BUILDING RETURN 34
TM 7 Installation & Service Manual Gas connections Connecting gas supply piping 1. Install ground joint union for servicing, when required. 2. On Models SNR150-100 -- SNA285-125 install a manual shutoff valve in the gas supply piping outside water heater jacket when required by local codes or utility requirements. 4. Support piping with hangers, not by the water heater or its accessories. WARNING 3. In Canada – When using manual main shutoff valves, it must be identified by the installer.
TM 7 Installation & Service Manual Gas connections WARNING Failure to apply pipe sealing compound as detailed in this manual can result in severe personal injury, death, or substantial property damage. WARNING Shield water heaters are typically shipped ready to fire on natural gas. Check the water heater rating plate to determine which fuel the water heater is set for. In order to operate on LP gas contact the factory, an orifice MUST BE installed or a gas valve adjustment MUST BE made.
TM 7 Gas connections Installation & Service Manual (continued) Table 7A Natural Gas Pipe Size Chart Natural Gas Pipe Capacity Chart Length of Pipe in Straight Feet for 1/2 PSI Nominal Iron Pipe Size (Inches) 1/2 3/4 1 1-1/4 1-1/2 2 2-1/2 3 4 10 20 175 120 369 256 697 477 1400 974 2150 1500 4100 2820 6460 4460 11200 7900 23500 16100 WARNING 30 97 205 384 789 1210 2260 3610 6400 13100 40 82 174 328 677 1020 1950 3100 5400 11100 50 N/A 155 292 595 923 1720 2720 4870 10000 60 N/A 141 267 543 830 1
Installation & Service Manual TM 7 Gas connections 17. Check burner performance by cycling the system while you observe burner response. The burner should ignite promptly. Flame pattern should be stable. Turn system off and allow burner to cool, then cycle burner again to ensure proper ignition and flame characteristics.
TM 8 Installation & Service Manual Field wiring WARNING ELECTRICAL SHOCK HAZARD – For your safety, turn off electrical power supply before making any electrical connections to avoid possible electric shock hazard. Failure to do so can cause severe personal injury or death. NOTICE Wiring must be N.E.C. Class 1. If original wiring as supplied with the water heater must be replaced, use only type 105°C wire or equivalent.
TM 8 Installation & Service Manual Field wiring 40 LOW WATER CUTOFF BUILDING MANAGMENT SYSTEM ALARM BELL Figure 8-3 Low Voltage Field Wiring Connections
Installation & Service Manual TM 8 Field wiring (continued) Figure 8-4 Control Inputs/Outputs TANK SENSOR LOW VOLTAGE CONNECTION BOARD INPUTS LOW WATER CUTOFF INLET TEMPERATURE SENSOR OUTLET TEMPERATURE / HIGH LIMIT SENSOR FLUE GAS SENSOR BLOCKED AIR INLET PRESSURE SWITCH FLAME SENSOR BLOCKED DRAIN SWITCH CONTROL BOARD DISPLAY PANEL LOW VOLTAGE CONNECTION BOARD ALARM BELL (ALARM CONTACTS) OUTPUTS RUNTIME CONTACTS WHR PUMP IGNITER BLOWER CONTROL BOARD GAS VALVE DISPLAY PANEL 41
TM 9 Installation & Service Manual Condensate disposal Condensate drain 1. This water heater is a high efficiency appliance that produces condensate. 2. Slope condensate tubing down and away from the water heater into a drain or condensate neutralizing filter. Condensate from the Shield water heater will be slightly acidic (typically with a pH from 3 to 5). Install a neutralizing filter if required by local codes. A Neutralizer Kit is available from the factory (KIT3087). 3.
TM 10 Installation & Service Manual Start-up Chlorine concentration less than 200 ppm WARNING 1. Do not fill the water heater or operate with water containing chlorine in excess of 200 ppm. 2. Filling with chlorinated fresh water should be acceptable since drinking water chlorine levels are much lower. 3. Do not use the water heater to directly heat swimming pool or spa water. 4. At initial fill and during water heater startup and testing, check system thoroughly for any leaks.
Installation & Service Manual TM 10 Start-up Start the water heater Check flame and combustion 1. Read and follow the Operating instructions in FIG.’s 10-2 and 10-3, pages 45 and 46. 1. Press the SHUTDOWN button on the display until HTR:Off appears in the display window. If water heater does not start correctly 2. Remove the screws securing the top panel to the unit. Remove the panel from the unit to gain access to the flue sensor. 1. Check for loose connections, blown fuse or service switch off.
TM 10 Start-up Installation & Service Manual (continued) Figure 10-2 Operating Instructions - Models SNR150-100 -- SNA285-125 45
TM 10 Start-up Figure 10-3 Operating Instructions - Models SNA400-125 -- SNA500-125 46 Installation & Service Manual
TM 11 Installation & Service Manual Operating information General How the water heater operates The Shield water heater combines an advanced stainless steel heat exchanger, electronic control module, and tank that allows fully condensing operation. The blower pulls in air and pushes flue products out of the heat exchanger and flue piping. The control module regulates blower speed to control the water heater firing rate.
TM 11 Installation & Service Manual Operating information Water heater temperature regulation Tank Differential Operating temperature (target) Once the tank set point is satisfied, the tank temperature must drop below the set point by this amount before the heater will fire again. The temperature range of this parameter is 3.6°F to 18°F. The default value is 6.3°F.
TM 11 Operating information Installation & Service Manual (continued) Sequence of operation OPERATION 1. When the tank temperature falls below the set point minus the differential, the control will start the burner. 2. The control connects 120 VAC to the blower. The blower does not run at this time. • The manual reset high limit must be closed before the control powers up the blower. • The control starts the internal pump. • If there is an external limit connected to the heater, it must be closed.
TM 11 Installation & Service Manual Operating information Shield control module Use the control panel (FIG. 11-1) to set temperatures, operating conditions, and monitor water heater operation. Figure 11-1 Control Panel • Press once to go into Menu Mode • Press again to exit Menu Mode • Press to toggle between digits when entering the hour, minutes, etc.
TM 11 Operating information Installation & Service Manual (continued) Status display screens Status Display Screens By using the Previous/Next ( , ) arrow keys on the electronic control module display panel, you can navigate through the five (5) display screens. Each screen will contain two (2) viewable items.
TM 11 Installation & Service Manual Operating information Status Display Screens (cont’d) By using the Previous/Next ( , ) arrow keys on the electronic control module display panel, you can navigate through the five (5) display screens. Each screen will contain two (2) viewable items. The following is a description of the individual items and what they can display: Screen #3 Display shows: Description RISE: ***.
TM 12 Installation & Service Manual Maintenance Maintenance and annual startup Table 12A Service and Maintenance Schedules Service technician Owner maintenance (see the following pages for instructions) General: • Address reported problems • Inspect interior; clean and vacuum if necessary; Daily • Clean condensate trap and fill with fresh water • Check water heater area ANNUAL START-UP • Check for leaks (water, gas, flue, condensate) • Verify flue and air lines in good condition and sealed tight
TM 12 Installation & Service Manual Maintenance WARNING Follow the service and maintenance procedures given throughout this manual and in component literature shipped with the water heater. Failure to perform the service and maintenance could result in damage to the water heater or system. Failure to follow the directions in this manual and component literature could result in severe personal injury, death, or substantial property damage.
TM 12 Maintenance Installation & Service Manual (continued) Flue vent system and air piping 1. Visually inspect the entire flue gas venting system and air piping for blockage, deterioration or leakage. Repair any joints that show signs of leakage. Verify that air inlet pipe is connected and properly sealed. 2. Verify that water heater vent discharge and air intake are clean and free of obstructions.
TM 12 Installation & Service Manual Maintenance Inspect ignition and flame sense electrodes 1. Remove the ignition and flame sense electrodes from the water heater heat exchanger access cover. 2. Remove any deposits accumulated on the ignition/flame sense electrode using sandpaper. If the electrodes cannot be cleaned satisfactorily, replace with new ones. 3. Replace ignition/flame sense electrode, making sure gasket is in good condition and correctly positioned.
TM 12 Maintenance Installation & Service Manual (continued) Handling ceramic fiber materials Cleaning heat exchanger REMOVAL OF COMBUSTION CHAMBER LINING 1. Shut down water heater: WARNING The combustion chamber door insulation in this product contains ceramic fiber material. Ceramic fibers can be converted to cristobalite in very high temperature applications.
TM 13 Installation & Service Manual Troubleshooting WARNING Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation. Always disconnect power to the water heater before servicing. Failure to comply could result in severe personal injury, death, or substantial property damage. WARNING Never jumper (bypass) any device except for momentary testing as outlined in the Troubleshooting chart.
TM 13 Troubleshooting Installation & Service Manual (continued) Table 13A Troubleshooting Chart - No Display FAULT CAUSE - No 120 VAC supplied to unit. CORRECTIVE ACTION • Check external line switch, fuse, or breaker. • Check wiring harness connection between display board and main control board. Connect harness at both points. No Display No Burner Operation Unit Does Not Modulate Above 50% - Bad display board. • Replace board. - Bad main control board. • Replace the main control board.
TM 13 Installation & Service Manual Troubleshooting Checking temperature sensors The water heater temperature sensors (inlet water, outlet water, tank water, and flue) are all resistance type devices. The following tables show the correct values for the sensors at various temperatures. Use an ohmmeter to read the resistance of the sensor at a known temperature. If the resistance of the sensor does not closely match its corresponding table, replace the sensor.
TM 13 Troubleshooting Installation & Service Manual (continued) Table 13D Troubleshooting Chart - Noisy System FAULT CAUSE CORRECTIVE ACTION - Supply gas problem. Natural gas pressures should be between 4 inches w.c. and • Refer to Section 7 - Gas Connections for detailed 14 inches w.c. LP gas pressures should information concerning the gas supply. be between 8 inches w.c. and 14 inches w.c. Noisy Operation No Pump Operation Relief Valve Opening - Gas/air mixture problem.
TM 13 Installation & Service Manual Troubleshooting Table 13E Troubleshooting Chart - Fault Messages Displayed on Water Heater Interface FAULT DESCRIPTION Flame Sequence (will require a manual The flame detector circuit is seeing a flame reset once the condition signal while no flame is present. has been corrected. Press the RESET button on the display to reset.) CORRECTIVE ACTION • Check supply voltage for proper polarity. • Check external wiring for voltage feedback.
TM 13 Troubleshooting Installation & Service Manual (continued) Table 13E (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Water Heater Interface FAULT DESCRIPTION CORRECTIVE ACTION • Inspect spark electrode and associated wiring for damage and connection. Reference page 56 of this manual for removal and cleaning procedures. Replace if necessary. • Check for proper electrical grounding of unit. • Check incoming supply gas pressure.
TM 13 Installation & Service Manual Troubleshooting Table 13E (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Water Heater Interface FAULT Manual Reset High Limit DESCRIPTION CORRECTIVE ACTION The outlet water temperature has exceeded • Verify that the system is full of water and that all air the fixed setting of the manual reset high has been properly purged from the system. limit. • Verify that the water heater is piped properly into the heating system.
TM 13 Troubleshooting Installation & Service Manual (continued) Table 13E (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Water Heater Interface FAULT Fan High OR Fan Speed High DESCRIPTION The actual fan RPM is 30% higher than • Vent/air intake lengths exceed the maximum allowed what is being called for. lengths. Refer to Section 2 - General Venting for proper lengths. • Check for obstruction or blockage in the vent/air intake pipes or at terminations.
TM 13 Installation & Service Manual Troubleshooting Table 13E (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Water Heater Interface FAULT DESCRIPTION CORRECTIVE ACTION • Verify that the system is full of water and that all air The temperature rise across the heat has been properly purged from the system. exchanger has exceeded the set • Verify that the water heater is piped properly into the parameters for the water heater. heating system.
TM 13 Troubleshooting Installation & Service Manual (continued) Table 13E (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Water Heater Interface FAULT DESCRIPTION CORRECTIVE ACTION • Establish a draw to remove HW heat from the water heater. • Verify that the system is full of water and that all air has been properly purged from the system. • Verify that the water heater is piped properly into the heating system.
Installation & Service Manual TM 13 Troubleshooting Combustion Analysis Procedure Table 13G Flue Products 1. Press the SHUTDOWN button on the display until HTR:Off appears in the display window. Natural Gas 2. Remove the screws securing the top panel to the unit. Remove the panel from the unit to gain access to the flue sensor. 3. Locate the flue sensor in the top of the vent connection. Remove the flue sensor and grommet from the unit. Note: Combustion measurements will be made at this point. 4.
TM 13 Troubleshooting Installation & Service Manual (continued) Gas valve adjustment procedure If adjustment of the gas valve is deemed necessary, use the following procedures: (Note: The procedures below are model specific.) Figure 13-3 Gas Valve Adjustment: Model SNA400-125 Models SNR150-100 -- SNA285-125 Locate the throttle adjustment screw on the side of the venturi valve (FIG. 13-2).
Installation & Service Manual TM 14 Diagrams Figure 14-1 Ladder Diagram JUNCTION BOX 120VAC NEUTRAL TERMINAL STRIP 120V SUPPLY "L" GROUND TERMINAL STRIP 120V SUPPLY "N" GND PUMP RELAY 4 DHW PUMP "L" 3 DHW PUMP "N" DHW PUMP TERMINAL STRIP INTEGRATED CONTROL X1-6 PUMP RELAY COIL X1-3 F5 2 5A TERMINAL STRIP 1 DHW PUMP RELAY BOX DEPICTS OPTIONAL ITEMS X1-8 BLOWER F4 JUNCTION BOX X1-1 3.5A BLOWER RELAY F3 1.25A 120 VAC X5-7 F2 X6-7 3.
Installation & Service Manual TM 14 Diagrams (continued) Figure 14-2 Wiring Diagram LOW VOLTAGE 120 VAC HIGH VOLTAGE DISPLAY WARNING DISCONNECT POWER BEFORE SERVICING INTEGRATED CONTROL JUNCTION BOX X3 PC INTERFACE BOX DEPICTS OPTIONAL ITEMS X8 OR CN1 CN2 X1-5 L N CONNECTION BOARD W W DHW PUMP GND PUMP RELAY 3 1 CN2-9 2 CN2-3 OR BK 1 X6-10 2 4 X6-5 X1-3 X1-6 OR BK BK L L N EXTERNAL LIMITS W GND GND 120V SUPPLY N TERMINAL STRIP ALARM CONTACTS CN2-7 5 CN2-1 6
Revision Notes: Revision A (ECO #C02299) initial release. Revision B (ECO #C02870) reflects the addition of a mixing valve to the piping diagrams (FIG.’s 6-2 and 6-3, pgs. 32 - 34). Revision C (ECO #C02738) reflects edits made to the Gas Valve Adjustment Procedure for Model SNA400-125 on page 69. Revision D (ECO #C03223) reflects edits made to the high altitude section on page 7.
