A.O. Smith GAHH 40 100 ユーザーズマニュアル

15

It is recommended that the tank be drained and flushed every 6 months to remove sediment which 

may build up during operation. The water heater should be drained if being shut down during freezing 

temperatures. To drain the tank, perform the following steps:

Adequate Drain

Hose

Outer Door

1.  Turn off the gas to the water heater at the manual gas shut-off valve and turn off the electrical power to  

 

the gas control/thermostat valve.

2.  Open a nearby hot water faucet until the water is no longer hot.
3.  Close the cold water inlet valve.
4.  Remove the outer door and connect a hose to the drain valve and terminate it to an adequate drain or  

 

external to the building (Figure 19).

5.  Open the water heater drain valve and allow all the water to drain from the tank. Flush the tank with  

 

water as needed to remove sediment.

6.  Close the drain valve, refill the tank, and restart the heater as directed in the lighting instructions on the  

 

front of the heater.

IMPORTANT: Condensation may occur when refilling the tank and should not be confused with a tank leak.

 

 

 

 

NOTE: If the water heater is going to be shut down for an extended period, 

             

 

 

 

the drain valve should be left open.