Resistant Water Heaters Gas Water Heaters SERVICE MANUAL Troubleshooting Guide and Instructions for Service (To be performed ONLY by qualified service providers) FEATURING For the Bradford White Defender Safety System ® Models: MI30T*F(BN,CX,SX) M430T*F(BN,CX,SX) MI30S*F(BN, CX,SX) M440T*F(BN, CX,SX) MI303T*F(BN,CX,SX) M4403S*F(BN,CX,SX)
National Excelsior Company www.excelsiorhvac.com The Bradford White DEFENDER Safety System ® Flammable Vapor Ignition Resistant Water Heaters Table of Contents Page Service Procedure Introduction - - - Trouble shooting Chart - - - Inner Door Gasket Removal, Inspection, Replacement and Installation...
The following information will instruct service professionals on the function, proper diagnosis and repair of water heaters employing the Bradford White DEFENDER Safety System. How the Safety System Works During normal operation, air for combustion is drawn into the water heater through the opening in the jacket.
National Excelsior Company www.excelsiorhvac.com White Rodgers/Robertshaw Gas Valve Troubleshooting Chart Flammable Vapor Ignition Resistant Water Heaters SERVICE SYMPTOM PROBABLE CAUSE CORRECTIVE ACTION PROCEDURE 1. Turn on gas supply and/or check line 1. See Service Procedure 1. No incoming gas or too low gas pressure.
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National Excelsior Company www.excelsiorhvac.com Honeywell Gas Control Troubleshooting Chart Flammable Vapor Ignition Resistant Water Heaters Observe green LED indicator on Gas Control. Error flash codes are displayed with a three second pause before repeating. Check and repair the system as noted in the Green LED Indicator troubleshooting table below.
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National Excelsior Company www.excelsiorhvac.com Honeywell Gas Control Troubleshooting Chart Flammable Vapor Ignition Resistant Water Heaters Observe green LED indicator on Gas Control. Error flash codes are displayed with a three second pause before repeating. Check and repair the system as noted in the Green LED Indicator troubleshooting table below.
National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-I DEFENDER Inner Door/Gasket Removal, Inspection Replacement and Reinstallation Safety System ® For Honeywell Control, rotate knob counter-clockwise to the “OFF” position. Inner Door Removal Procedure Step 1. Rotate knob of the combination thermostat/gas valve to the “OFF”...
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-I Inner Door/Gasket Removal, Inspection Replacement and Reinstallation GASKET OVERLAP MUST RECOMMENDED PATTERN BE AS SHOWN ENLARGED FOR RTV SEALANT ±1/32" VIEW OF FLANGE AREA PLACE FLANGE SECTIONS FIRST VIEW WITH GASKETS IN PLACE EXPANDED VIEW Installation of Inner Door With Gasket.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-I Inner Door/Gasket Removal, Inspection Replacement and Reinstallation Step 10. Firmly place right side inner door flange against the left side inner door flange and secure with (2) hex drive screws from step 3c. DO NOT OVER TIGHTEN SCREWS. Step 11.
National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-II DEFENDER Thermocouple/Thermopile Testing and Replacement Safety System ® CLOSED CIRCUIT THERMOCOUPLE TESTING (White Rodgers Control) Step 1. Closed circuit testing is the preferred method for testing thermocouple. Following the lighting instruction label on the heater, proceed to light the pilot and allow to operate for three minuets.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-II Thermocouple/Thermopile Testing and Replacement OPEN CIRCUIT THERMOCOUPLE TESTING (White Rodgers/Robertshaw Gas Valve) Step 1. Disconnect thermocouple from combination thermostat/gas valve. Step 2. Using a multimeter capable of measuring millivolts, connect one alligator clip to the end ball or contact portion of the thermocouple, and the other alligator clip to copper portion of the thermocouple.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-II Thermocouple/Thermopile Testing and Replacement OPEN CIRCUIT THERMOPILE TESTING (Honeywell Gas Control) The following test should be performed while the pilot flame is on. Step 1. Turn knob to pilot position and depress. Step 2. Continue pressing knob and remove red (+) wire from resettable thermal door switch.
National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-III DEFENDER Pilot Assembly Inspection, Cleaning and Replacement Safety System ® PILOT/ELECTRODE ASSEMBLY INSPECTION, For Honeywell Control, rotate knob counter-clockwise to the CLEANING AND REPLACEMENT “OFF” position. Step 1. Turn off gas supply to water heater. Rotate knob...
National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-IV DEFENDER Piezo Igniter, Electrode Testing and Replacement Safety System ® PIEZO IGNITER, ELECTRODE TESTING AND REPLACEMENT With the pilot not in operation (no pilot flame) you can check the Piezo and electrode circuit by viewing pilot thru the sight glass located on the inner door and observing the spark action.
National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-V DEFENDER Gas Valve Testing and Replacement (White Rodgers/Robertshaw) Safety System ® Gas Valve Testing and Replacement (White Rodgers/Robertshaw) The gas valve is a non repairable device. If trouble shooting has determined a problem with the gas valve, it must be replaced.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-V Gas Valve Testing and Replacement (White Rodgers/Robertshaw) THERMOCOUPLE TESTING See SERVICE PROCEDURE RG-II MAGNET ASSEMBLY TESTING (White Rodgers Control) Step 1. Following the lighting instruction label on the heater, proceed to light the pilot and allow to operate for three minuets.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-V Gas Valve Testing and Replacement (White Rodgers/Robertshaw) ECO (Energy Cut Off) TESTING Step 1. Disconnect thermocouple from gas valve. Step 2. Using a multimeter capable of measuring Ohms (or continuity), attach one lead (alligator clip) to the pilot tube. Insert the other lead (probe) fully into the magnet opening, Be sure the probe makes contact only at the top center of the magnet opening.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-V Gas Valve Testing and Replacement (White Rodgers/Robertshaw) Step 7. Removal of gas valve. a) Disconnect main burner feedline, pilot tube and thermocouple from gas valve & remove burner from combustion chamber. NOTE: Feed line nut for natural gas control uses right hand threads, LP control uses left hand thread.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-V Gas Valve Testing and Replacement (White Rodgers/Robertshaw) Step 9. Reinstallation of inner door assembly. (cont.) b) Clean any gasket residue or other debris from combustion chamber surface before installing the inner door/gasket assembly. c) Position thermocouple, pilot tube and Piezo wire against left side inner door flange gasket.DO NOT ROUTE THROUGH RADIUSED CHANNEL WITH FEEDLINE.
National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® Honeywell Gas Control Testing, Disassembly, and Replacement The Gas Control is made up of (5) major components; the control cover, the piezo igniter, the valve body, the temperature sensor, and the back plate.
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National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® MANIFOLD PRESSURE TESTING (this procedure presumes a maximum line pressure of 14.0" w.c.) Step 1. Set the Gas Control to the “OFF” position.
National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® TEMPERATURE SENSOR TESTING CAUTION DO NOT use standard multimeter probes for this test. Doing so will damage connector. Use special pin type...
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National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® WARNING Stored water may be HOT when performing the following steps in this procedure. Take necessary precaution to prevent personal injury.
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National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® GAS CONTROL DISASSEMBLY/REASSEMBLY Step 1. Rotate knob of the Gas Control to the “OFF” position. Step 2. Turn off gas supply to water heater.
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National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® GAS CONTROL DISASSEMBLY/REASSEMBLY Step 8. Disconnect temperature sensor from control board and remove wire from the temperature sensor wire routing clip.
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National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® GAS CONTROL DISASSEMBLY/REASSEMBLY Step 10. Remove the valve body by removing screw located at the lower left corner then unclipping the lower right side from the backplate first followed by the lower left side using a flat head screwdriver.
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National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® GAS CONTROL DISASSEMBLY/REASSEMBLY Step 12. Remove temperature sensor from insertion stick by pulling apart as illustrated below. Temperature sensor...
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National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® GAS CONTROL REPLACEMENT Rotate knob counter-clockwise to the “OFF” position. Step 1. Rotate knob of the Gas Control to the “OFF” position.
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National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® GAS CONTROL REPLACEMENT Step 8. Install new Gas Control into water heater (contintued). b) Reattach main burner feedline, pilot tube, piezo igniter wire, inner door wire (red) and thermopile wire (white) to Gas Control.
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National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-VI DEFENDER Gas Control Testing, Disassembly & Replacement (Honeywell) Safety System ® GAS CONTROL REPLACEMENT Step 9. Reinstallation of inner door assembly (continued). d) Firmly place right side inner door flange against the left side inner door flange and secure with (2) hex drive screws from step 6c.
Under no circumstances shall flammable materials be used or stored in the vicinity of the water heater. With the inner door removed the Bradford White Defender Safety System will be inactivated. If flammable vapors are present, a fire or explosion may result causing property damage, personal injury or death.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-VII Burner Operation Inspection, Adjustment Cleaning and Replacement MAIN BURNER: Inspection, Adjustment, Cleaning and Replacement (cont.) Step 3. Fully inspect inner gasket per SERVICE PROCEDURE RG-I, step 4. Replace gasket if required following SERVICE PROCEDURE I, steps 5 & 6. Step 4.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-VII Burner Operation Inspection, Adjustment Cleaning and Replacement BURNER CLEANING (Cont.) Step 5. Disconnect (unscrew) Main burner (steel) from main burner orifice or on cast iron burners (“C” burner), loosen air shutter & disconnect (unscrew) feedline from burner. Step 6.
National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-VIII The Bradford White Resettable Thermal Switch DEFENDER Testing and Replacement Safety System ® RESETTABLE THERMAL SWITCH CONTINUITY TESTING Step 1. Remove outer jacket door. Step 2. Disconnect wire leads from resettable thermal switch.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-VIII Resettable Thermal Switch Testing and Replacement RESETTABLE THERMAL SWITCH REPLACEMENT Step 1. Rotate knob of combination thermostat gas valve to the off position. For White Rodgers Control, depress knob slightly and rotate clockwise to the “OFF” position. For Honeywell Control, rotate knob counter-clockwise to the “OFF”...
National Excelsior Company www.excelsiorhvac.com The Bradford White SERVICE PROCEDURE RG-IX ScreenLok Flame Arrestor Cleaning DEFENDER ® Safety System ® ScreenLok ® Flame Arrestor Cleaning Step 1. Rotate knob of combination thermostat gas valve to the off position. For White Rodgers Control, depress knob slightly and rotate clockwise to the “OFF”...
National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-X The Bradford White Dip Tube and Anode DEFENDER Inspection and Replacement Safety System ® DIP TUBE INSPECTION AND REPLACEMENT WARNING Heater components and stored water may be HOT when performing the following steps in this procedure.
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National Excelsior Company www.excelsiorhvac.com SERVICE PROCEDURE RG-X Dip Tube and Anode Inspection and Replacement ANODE INSPECTION AND REPLACEMENT WARNING Heater components and stored water may be HOT when performing the following steps in this procedure. Take necessary precaution to prevent personal injury. Step 1.
National Excelsior Company www.excelsiorhvac.com The Bradford White DEFENDER Generic Parts List Safety System ® Draft Hood 16 Complete BN Burner Assembly (Natural) Hot Water Outlet/Anode 17 BN Burner Only Cold Water Inlet Tube 18 Main Burner Orifice Flue Baffle 19 Pilot Assembly T&P Relief Valve...
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National Excelsior Company www.excelsiorhvac.com Email parts@bradfordwhite.com techserv@bradfordwhite.com www.bradfordwhite.com Subject to change without notice.