10. Replace the outer door (see item K page 10).
Door Gasket | Burner |
| Slot |
Viewport | Manifold Tab |
FIGURE 40. | |
Removing and Replacing the Gas Control Valve/Thermostat
IMPORTANT: Use only factory authorized replacement parts.
Removing the Gas Control Valve/Thermostat:
1.Set the gas control valve/thermostat to its lowest setting by first depressing the COOLER 
and HOTTER
buttons together and hold for 1 second. Then press the COOLER
button until the VAC indicator light appears (Figure 32).
2.Unplug the water heater from the wall outlet.
3.Turn off the gas supply to the water heater at the manual gas
4.Drain the water heater. Refer to the section of “Draining and Flushing” section and follow the procedure.
5.Disconnect the the flame sense/hot surface igniter wire, power supply transformer, pressure switch/fan and display connector wires from the thermostat (Figure 35). Disconnect the manifould tube at the thermostat (Figure 35).
6.Refer to “Gas Piping” section (Figure 12) and disconnect the ground joint union in the gas piping. Disconnect the remaining pipe from the gas control valve/thermostat.
7.To remove the gas control valve/thermostat, thread a correctly sized pipe into the inlet and use it to turn the gas control valve/ thermostat (counterclockwise.) Do not use pipe wrench or equivalent to grip body. Damage may result, causing leaks. Do not insert any sharp objects into the inlet or outlet connections. Damage to the gas control valve/thermostat may result.
Replacing the Gas Valve:
1.To replace the gas control valve/thermostat, reassemble in reverse order. When replacing the gas control valve/ thermostat, thread a correctly sized pipe into the inlet and use it to turn the gas valve (clockwise.) DO NOT OVER TIGHTEN or damage may result. NOTE: Use an approved TEFLON® tape or pipe compound only on the threaded section of the gas control valve/thermostat that screws into the tank.
2.Reconnect the gas piping to the gas control valve/ thermostat. NOTE: Use an approved Teflon tape or pipe compound on the gas piping connections.
3.Reconnect the manifold tube, flame sense/hot surface igniter wire, power supply transformer, pressure switch/fan and display connector wires (Figure 35).
4.Fill the tank completely with water. NOTE: To purge the lines of any excess air, keep the hot water faucet open for 3 minutes after a constant flow of water is obtained.
5.Turn on the gas supply and test the gas supply connections by brushing on an approved noncorrosive leak detection solution. IMPORTANT: Do Not splash solution onto the electrical connections. Bubbles forming indicate a leak. Correct any leak found.
6.Check the operation of the burner by following the lighting instructions on the front of the water heater. With the burner lit, check the gas control valve/thermostat supply line, manifold tube connections for leaks.
7.Verify proper operation and then replace the outer door.
TEFLON® is a registered trademark of E.I. Du Pont De Nemours and Company
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