Originally Posted by rideandslide
What is the correct ration and procedure for sanitizing the FWT ???
Be sure to note the different bleach amounts to be used based on the sodium hypochlorite concentration. Most bleach available in stores is 8.25%. The procedure below gives you the dose required for both 5.25 and 8.25%. Too much bleach can be harmful to the plumbing system.
Use the gravity fill to perform this task. Remove cap from the gravity fill. Add the solution. When finished, secure the gravity fill cap. If you don't have gravity fill use the winterizing pick up tube to introduce the solution to your system.
1) Remove the water line connections and connect the bypass hose to the water lines on water filter. If you don't have a bypass just remove the filter and replace the housing or pump it through the city water fill line.
2) Prepare a household chlorine bleach solution of 1 gallon water and 1⁄4 cup of chlorine bleach (see not at bottom concerning bleach strength). Use 1 gallon of solution for every 15 gallons of tank capacity. E.g.: Add 2-2/3 gallons solution to a 40 gallon tank. This mixture puts a 50 ppm (parts per million) residual in the water system, and acts as a quick-kill dosage for harmful bacteria, viruses and slime- forming organisms. Concentrations higher than 50 ppm may damage the water lines and/or tanks.
3) Turn the water pump OFF.
4) Close the water heater bypass valve. The bypass valve is located behind the water heater. This ensures that none of the prepared disinfecting solution enters the water heater. Refer to the water heater OEM instructions on ushing the water heater.
5) Drain the fresh water tank. Water tank drain is located in the roadside water service center. Close the drain and pour the solution into the fresh water tank using the gravity ll and a funnel.
6) Turn the water pump ON. Open each faucet, in turn, and run the water until you smell a distinct chlorine bleach odor. Do not forget the hot water, tub and shower faucets. Allow the system to stand for 4 hours.
7) Drain the system and ush with fresh water. The water tank and low point drains are located in the roadside water service center. Flush with fresh water repeatedly until the water system no longer smells or tastes like chlorine bleach.
8) Install new water filter.
9) Remove bypass hose and store. Reconnect water lines to water filter.
Use the same hose labeled for potable water to introduce the chlorine solution into the system. This will disinfect the potable water hose at the same time. Several flushes are required to remove chlorine residue from the potable hose.
Household bleach is 5.25% Sodium Hypochlorite. Higher concentration will increase PPM ratio. If using 8.25% Sodium Hypochlorite (typical to laundry bleach) reduce from 1/4 cup per gallon of solution to 2.5 tablespoons per gallon of solution.
As noted earlier by 007 you can skip bypassing the water heater and sanitize it as well.