If you don't have a problem with algae or slime
in your tank, and just want to make sure all the
bacteria are removed:
Make sure the water heater is turned off.
Fill the water tank half-way.
In a gallon of water, dilute 6 ounces (2/3 cup)
of chlorine bleach for each 10 gallons of fresh
water capacity (including hot water tank). This
is a stronger solution than the 4 ounces per 15
gallons generally recommended, but is a 200 ppm
disenfectant solution recommended by the EPA.
Add the solution to the fresh water tank.
Fill the fresh water tank. This will mix the solution
in the tank. If you want, you can even drive around
the block to really mix it up.
Make sure the water system is pumping from the tank
and not an external fresh water supply.
Each water outlet (faucet or showerhead) should
be opended, one at a time, to let the treated water
run through. Make sure you run the treated water
through both cold and hot water lines. Run the water
until the the chlorine smell is noticeable. This
will probably take a couple of minutes. At one hour
intervals, repeat this step until the smell of the
chlorine is immediately noticeable.
Completely drain the fresh water tank and the hot
water tank by opening all plumbing drains and the
hot water tank drain plug.
Close all valves and faucets and drain plugs.
Fill water tank with fresh water and run water through
all outlets (hot and cold) until the smell of chlorine
is gone.
Flush each faucet for several minutes each repeating
until the tank is again empty.
Fill the tank again. The water should now be safe
to drink but if the chlorine odor is too strong
you can add a mixture of 1/2 cup of baking soda
and a gallon of water to the fresh water tank. Repeat
the fresh water flush.
Your fresh water system should now be safe for use.
If
you need to remove slime or algae from your fresh
water system, before you sanitize the system do
the following:
Following the procedures used above, flush the fresh
water system with a solution of household detergent
and water. Use 4 teaspoons of detergent for every
10 gallons of fresh water capacity.
Run the water full force through all outlets until
the tank is empty. Refill the fresh water tank and
run the fresh water through all outlets.
You are now ready to start the sanitizing procedures
listed above.