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Water Conservation
How to Chlorinate Water Heater and Storage Tanks
- Turn off gas or electric supply to water heater.
- Turn off cold water supply valve to water heater or tank.
- Open nearby hot water faucet to allow air into system. This will break vacuum and allow heater or tank to drain.
- Drain all water from tank. (A hose attached to the drain valve may be needed to direct water to a nearby drain.)
- Remove anode rod(s) and close drain valve.
- Using a funnel placed in the anode rod opening, pour in one gallon of household chlorine bleach (i.e., Clorox or Purex) for every 25 gallons of tank capacity.
NOTE: For commercial systems using large diameter pipe and long hot water loops, estimate water volume and add additional chlorine at the same one gallon to 25 gallons ratio.
- Reinstall anode rod(s) after inspecting and replacing as needed.
- Open cold water supply valve and refill system with water. Draw chlorine solution into hot water system piping by bleeding water at each faucet until the chlorine solution can be smelled. Operate dishwashers and clothes washers first until chlorine is smelled in those appliances. It is important to chlorinate all hot water lines.
- Leave chlorine solution undisturbed in the hot water heating system one hour or more.
- After the recommended contact time has been allowed, drain chlorine solution in tank according to steps #2, #3, and #4.
- Close drain valve and refill tank. Allow tank to sit for 15 minutes. Repeat steps #2, #3, and #4. Continue to flush tank if water is discolored or has chlorine odor.
- Close drain valve and refill tank. Flush all chlorine from piping by running hot water faucets until no chlorine odor is detected. Operate dishwashers and clothes washers empty for one complete cycle.
- Return hot water heating system to duty by following recommended start-up procedure posted on the heater or in the service manual.
