Bradford-White Corp 50T65F(BN, CX)2, Flammable Vapor Ignition Resistant Water Heater, M1XR403S*F(BN, M1XR504T*F(BN, M2C504T*F(BN, M2XR504T*F(BN, M430T*F(BN, M4403S*F(BN, M4403T*F(BN, M450S*F(BN, MI303T*F(BN, MI30S*F(BN, MI30T*F(BN, MI403S*F(BN, MI404T*F(BN, MI40T*F(BN, MI503*F(BN, MI504S*F(BN, MI50L*F(BN ScreenLok Flame Arrestor Cleaning

ScreenLok Flame Arrestor Cleaning

Step 1. Rotate knob of combination thermostat gas valve to the off position.

Step 2. Remove outer jacket door.

Step 3. Remove inner door per SERVICE PROCEDURE RG-I, step 3a through 3e.

Step 4. Disconnect main burner feed line (3/4 wrench), pilot tube (7/16 wrench)

and thermocouple (3/8) wrench from combination thermostat gas valve

and remove burner assembly from combustion chamber.

Step 5. Clean ScreenLok Flame Arrestor using stiff brush, compressed air and/or

shop vacuum to remove any scale or other debris accumulation. Using a

soft brush, clear jacket openings from any dirt, dust, restrictions or other obstructions.

Step 6. Remove any debris from burner assembly per SERVICE PROCEDURE RG-V and reinstall burner

assembly into combustion chamber.

Step 7. Reconnect feedline, thermocouple and pilot tube to the combination thermostat/gas valve.

Step 8 Reinstall inner door per SERVICE PROCEDURE RG-I, steps 4 through 13.

Step 9. To resume operation follow the instructions located on the lighting instruction label or the lighting

instruction located in the installation and operation manual.

SERVICE PROCEDURE RG-VIII

ScreenLok Flame Arrestor Cleaning

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Contents

Main SERVICE MANUAL Flammable Vapor Ignition Resistant Water Heater Troubleshooting Guide and Instruction for Service For the Bradford White Defender Safety System Models: Table of Contents Introduction The Bradford White DEFENDER Safety System How the Safety System Works SYMPTOM PROBABLE CAUSE CORRECTIVE ACTION Pilot Will Not Light Troubleshooting Chart Flammable Vapor Ignition Resistant Water Heaters Inner Door Removal Procedure Inner Door Gasket Replacement Procedure Installation of Inner Door with Gasket Page SERVICE PROCEDURE RG-II Thermocouple Testing and Replacement Closed Circuit Thermocouple Testing Open Circuit Thermocouple Testing SERVICE PROCEDURE RG-II Thermocouple Testing and Replacement Thermocouple Replacement SERVICE PROCEDURE RG-III Pilot Assembly Inspection, Cleaning and Replacement Pilot/Electrode Assembly Inspection, Cleaning and Replacement SERVICE PROCEDURE RG-IV Piezo Igniter, Electrode Piezo Igniter, Electrode Testing and Replacement Combination Thermostat/Gas Valve Testing and Replacement LINE PRESSURE MANIFOLD PRESSURE TES TING THERMOCOUPLE TESTING MAGNET ASSEMBLY TESTING ECO (Energy Cut Off) TESTING COMBINATION THERMOSTAT/GAS VALVE REPLACEMENT Page A seal breach may result in a fire or explosion causing property damage, personal injury or death. MAIN BURNER: Inspection, Adjustment, Cleaning and Replacement CAST IRON BURNER ADJUSTMENT !DANGER WARNING MAIN BURNER: Inspection, A djus tment, Cleaning and R eplacement BURNER CLEANIN G BURNER CLEANING(cont.) RESETTABLE THERMAL SWITCH CONTINUITY TESTING SERVICE PROCEDURE RG-VII Resettable Thermal Switch Page ScreenLok Flame Arrestor Cleaning SERVICE PROCEDURE RG-VIII ScreenLok Flame Arrestor Cleaning Dip Tube Inspection and Replacement SERVICE PROCEDURE RG-IX Dip Tube and Anode Inspection and Replacement Anode Inspection and Replacement SERVICE PROCEDURE RG-IX Dip Tube and Anode Inspection and Replacement PARTS LIST