Rheem P-M406 Operating Instructions - Page 42

LO NOx HEATERS (CONTINUED) MAIN BURNER AND ORIFICE REMOVAL BAFFLE MOUNTED INLET SIDE PILOT LOW NOx BURNER BURNER HOLD-DOWN BRACKET COMBUSTION AIR BLOWER GAS ORIFICE GAS VALVE 1. Remove burner tray, following above procedure. 2. Remove pilot. See pilot removal procedure. 3. Remove (8) total screws from the burner hold- down brackets, front and rear of tray. 4. Remove (8) total screws from the left and right sides of the manifold assembly. Detach the air/gas manifold assembly from the burner tray assembly. 5. Remove burners by raising them straight up off the rear end slots. 6. Use a long 9/16" socket wrench to remove orifice from the gas manifold. 7. Reverse above procedure to reinstall. Electrode Alignment Detail 207-407 Lo NOx Burner Tray BURNER TRAY REMOVAL 1. Shut off main electrical power switch to heater. 2. Shut off gas upstream of heater. 3. Remove front door. 4. Disconnect gas line from gas valve. 5. Remove (2) screws that mount burner tray to the base of the unit, and (2) screws that mount the blower box to the burner tray, and (1) screw that secures the anti-rotation bracket to the heater. 6. Disconnect wires that terminate at gas valve. 7. Unscrew (4) screws that secure the control box. 8. Disconnect pilot wire from the pilot assembly. 9. Disconnect wire connector from the combustion blower. 10. Carefully slide out the burner tray assembly. 11. Reverse above procedure to reinstall. GAS VALVE REMOVAL 1. Remove burner tray, following above procedure. 2. Disconnect, pilot tubing from gas valve. 3. Remove (2) screws that mount anti-rotation bracket to the burner tray. 4. Turn vertical gas pipe from manifold slightly and unscrew gas valve. 5. Reverse above procedure to reinstall. Lo NOx Horizontal Pilot PILOT REMOVAL 1. Disconnect pilot tubing from gas valve. 2. Remove the pilot wire from the pilot assembly. 3. Remove (2) screws that mount the pilot assembly to the burner tray. 4. Pull the pilot assembly downwards and outwards. 5. Reverse above procedure to reinstall. COMBUSTION BLOWER REMOVAL 1. Remove the (2) screws that secure the blower box to the burner tray. 2. Remove (2) screws that mount the blower box to the base of the heater. 3. Disconnect wire connector from the combustion blower. 4. Carefully remove blower box with combustion blower. 5. Remove (2) screws that secure combustion blower to blower box. 6. Reverse above procedure to reinstall. 42