A.O. Smith GAHH 40 100 ユーザーズマニュアル

29

g

COOLER

HOTTER

Electronic Control Display

ON/OFF 

SWITCH

ON

OFF

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: Ratchet with 

5/16

” Socket or 

5/16

” Nut 

Driver, Phillips Head Screwdriver.

Removing the Transformer:
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 40).

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 41). 

3.  Disconnect the electric connection by unplugging 

the transformer from the wall outlet (Figure 41).

4.  Remove the manifold cover outer door from the 

heater by depressing on the lower portion and 

pulling outward.

5.  Unplug the power supply transformer connector 

from the bottom of the gas control valve by 

pressing the snap connector and pulling 

downward (Figure 42). (NOTE: The transformer is 

located inside the transformer box adjacent to the 

gas control/thermostat valve).

6.   Using a phillips head screwdriver, remove the 

transformer box from the side of the water heater 

by removing the single screw securing it to the 

water heater’s side (Note: keep screw in a safe 

place for reinstalling later).

7.  Using a phillips head screwdriver remove the 

ground screw from the inside of the transformer 

box (Note: save the screw for reinstallation later) 

(see Figure 43).

8.  Take note of the position of the transformer, use 

a 5/16” nut driver or a ratchet with a 5/16” socket 

to remove the 2 hex head screws on the front of 

the transformer box (Note: save the screws for 

reinstallation later) (see Figure 43).

9.  Unplug the two flag terminal electrical connections 

on the transformer and pull the wiring and 

connector through the wire protector (Figure 43).

    Gas Valve
Wire Connector

   Gas Control
Valve/Thermostat