Component Replacement Instructions
505e/o
1. Turn off the gas supply.
2. Turn off the 120 V power supply.
3. Turn off the water supply. Drain all water
from the appliance.
4. Remove four screws securing the front panel.
Remove front panel.
Remove Fan Assembly (Figure 37)
5. Disconnect wire harness at the fan assembly.
Disconnect the air temperature thermistor
(two white wires) at the connection with the
white and orange wires within the wire
bundle.
6. Pull out the harness attached to the solenoid
on the manifold to make room to pull out the
fan assembly.
7. Remove the 2 screws that attach the fan
assembly to the bottom of the burner.
8. Pull out the fan assembly.
9. Remove 1 screw from the water outlet
bracket. Remove the bracket by rotating and
moving it up toward the bend in the tube
where the diameter is smaller.
10. Remove 2 screws and 2 brackets at the
bypass servo assembly.
Fan Assembly
Gas Manifold
Burner cover
plate
PC Board
Gas Control
Valve
Figure 36
Wire
harness
connection
Solenoid
Figure 37
Figure 38
Water outlet
connection
Bypass servo assembly
connections
Disconnect Water Lines (Figure 38)
On-Demand Gas Tankless Water Heater Service Manual
38
Heat Exchanger
2 screws
