11.Ensuring that the gas supply line is turned off, disconnect the gas piping at the ground joint union, then remove the gas piping from the gas control valve/ thermostat (Figure 116).
12.Remove any other fittings that may be installed on the threaded pipe to the gas control valve/thermostat (Figure 116).
13.After ensuring the water heater is completely drained, thread a short length of 1/2” threaded pipe into the inlet connection of the gas control valve/thermostat and use it to turn the gas control valve/thermostat counterclockwise to remove (Figure 117).
Installing the Gas Control Valve/Thermostat:
14.Before installing, apply Teflon® tape or an approved pipe sealant on the threads of the new gas control valve/thermostat (only the threads that screw into tank).
15.Thread a short length of 1/2” threaded pipe into the inlet connection of the new gas control valve/ thermostat and use it to turn the gas control valve/ thermostat clockwise to tighten into place (Note: Do Not over tighten or damage may result, but it needs to be water tight (Min. 35 foot pounds) (Figure 117).
16.Remove the 1/2” threaded pipe from the gas control valve/thermostat.
17.Reconnect the gas piping to the gas control valve/ thermostat, use Teflon® tape or an approved pipe sealant on threads of the piping (Figure 116).
18.Close the drain valve and turn on the cold water supply line filling the tank completely with water. Purge the water lines of any excess air by opening a hot water faucet allowing the water to flow for a minimum of 3 minutes, allowing the tank to fill completely.
19.Using the two (2) phillips head screws removed earlier in step 10, reattach the air pressure switch (orientation with pressure tubing connector to the down side) to the front of the water heater. Reattach the electrical flag terminal to the pressure switch. Reattach the pressure tubing (Figure 118).
20.Reinstall the transformer box to the front of the water heater by using the one (1) phillips head screw removed earlier in step 9 (Figure 118).
21.Reconnect the manifold tube to the gas control valve/ thermostat (Note: Do Not apply any thread sealant at this connection). To prevent any cross threading the manifold tube should be started by hand (turn clockwise
22.Reconnect all the electrical connections to the bottom of the gas control valve/thermostat, gently pushing each connector up snapping into place (Figure 119).
Teflon® is a registered trademark of E.I. Du Pont De Numours and Company.
Figure 116.
GAS
GROUND JOINT UNION
GAS PIPING 
| ROTATE TO: | |
Figure 117. | ROTATE TO: | |
GAS CONTROL VALVE / | INSTALL | |
THERMOSTAT | ||
| ||
| REMOVE | |
SHORT LENGTH OF |
| |
1/2” TREADED PIPE |
|
Figure 118. |
PRESSURE |
SWITCH |
MANIFOLD |
TUBE |
SCREW AT |
TRANSFORMER |
BOX |
Figure 119.
IMPORTANT: |
|
|
WHEN BRUSHING ON AN |
| GAS CONTROL |
APPROVED NONCORROSIVE |
| |
LEAK DETECTION SOLUTION, |
| VALVE/THERMOSTAT |
DO NOT SPLASH SOLUTION |
|
|
ONTO ELECTRICAL CON- |
|
|
NECTIONS. |
|
|
|
| PRESSURE |
MANIFOLD TUBE |
| SWITCH/FAN, |
| FV SENSOR | |
POWER SUPPLY | IGNITER/ | CONNECTOR |
| ||
TRANSFORMER | FLAME |
|
CONNECTOR | SENSE | DISPLAY, ANODE |
| CONNECTOR | ROD CONNECTOR |
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