Component Replacement Instructions
705e/o (ASME), 705i (ASME)
1. Turn off the gas supply.
2. Turn off the 120 V power supply.
3. Remove four screws securing the front panel.
Remove front panel.
4. Remove the surge protector (2 screws)
5. Remove the 2 screws connecting the PC
board to the water heater casing.
6. Pull out the PC board and remove the
connections.
7. Adjust dip switches on the new PC board.
8. Attach connections and insert PC board.
Attach with 2 screws.
9. Attach the surge protector
with 2 screws.
10. Perform the Gas Pressure
Setting Procedure.
Figure 16
Screw
SW1
SW2
Burner test point
Potentiometer
Surge
protector
Screw
Switches 1-8 (SW1):
Configure the dip switches the same as on the
original PC board. If necessary, refer to the
Dip Switch section or to the Operation and
Installation Manual for more information on
these dip switches.
Switches 1-4 (SW2) or Switches 1-6 (SW2):
Configure according to the diagrams based on
your model and gas type.
Propane (LPG) Natural Gas (NG)
SW2 setup for 705i
Switch No.
F
O
F
5
6
4
3
ON
1
2
Switch No.
F
O
F
5
6
4
3
ON
1
2
Propane (LPG) Natural Gas (NG)
SW2 setup for 705e/o
Switch No.
F
O
F
5
6
4
3
ON
1
2
Switch No.
F
O
F
5
6
4
3
ON
1
2
PC Board
On-Demand Gas Tankless Water Heater Service Manual
29
Screw