A.O. Smith 12 40GPC T 100 - Manual (Page 31)

31
AIR INTAKE CHAMBER BOX REMOVAL / REPLACEMENT
Important: Use only factory authorized replacement
parts. If you lack the necessary skills to properly
perform the installation, you should not proceed, but
get help from a qualified service technician.
Tools required: Phillips Head Screwdriver.
Removing the Air Intake Chamber Box:
1. Set the gas control valve/thermostat to its lowest
setting by pressing the “COOLER” and “HOTTER”
buttons together at the same time holding for 1
second. Then press the “COOLER” button to the
lowest setting (Figure 45).
2. Turn gas control switch to the “OFF” position
(located right side of the gas control valve/
thermostat) and turn off the gas supply to the unit
(Figure 46).
3. Disconnect the electric connection by unplugging
the transformer from the wall outlet (Figure 46).
4. Remove the manifold cover/ outer door from the
unit by depressing on the lower portion and pulling
outward.
5. Unplug the 3-wire pressure switch/fan/sensor
electrical connection of the wiring harness from
the gas control valve/thermostat by depressing the
lower portion of the snap clip to open and pulling
down the connector (Figure 47).
6. Using a phillips head screwdriver remove the 2
screws of the air intake chamber screen (Note:
save screws for reinstallation later) (Figure 48).
7. Remove the air intake chamber screen by lifting
upward and outward (Figure 48).
8. Please take note of the wire position routing
around the fan inside the air intake chamber as
this wire positioning will need to be duplicated
upon installation of the fan in the new intake
chamber box.
9. Remove the 2 screws securing the fan inside
the chamber (Note: save these screws for
reinstallation later) (Figure 48).
10. Lift the fan up and outward to remove from the air
intake chamber (Figure 48).
11. Locate the male to female electrical connection
with close pin lock on wiring harness (the
white connection approximately 12” from fan)
(Figure 48).
12. To separate the electrical connection of the fan
and wiring harness: press down on the back
portion of the close pin lock of the electrical
connection while pulling the connection in the
opposite directions.
13. Using a phillips head screwdriver, remove the 4
screws securing the air intake chamber box to the
water heater’s side (also keeping these screws in
a safe place for reinstallation later) (Figure 48).
GAS CONTROL
VALVE/THERMOSTAT
PRESSURE
SWITCH/FAN,
FV SENSOR
CONNECTOR
Figure 47.
Figure 48.
SCREEN FAN
AIR INTAKE
CHAMBER BOX
RUBBER WIRE
PROTECTOR
g
COOLER HOTTER
Electronic Control Display
Figure 45.
ON/OFF
SWITCH
ON
OFF
Figure 46.
UNPLUGGED