Tanklets > Water Hammer

Q: Good morning.... I saw your section on the Web site hoping you can help solve a problem I am experiencing, I own a 40-gallon gas hot water heater. Although I am not sure of the age, it has been in my home five years. It is in fine working condition.

I have been having problems with banging water pipes. The town has sent workmen in to check for air pockets, and they have flushed the system including the outside fire hydrants. I have put on expansion tubing, hung pipe hangers -- everything you can think of to stop the loud sounds that ring through the days-nights. It seems to start banging when the water returns into the tank.

I have been working on this matter for some time. The utility company is now scratching their heads. They are as lost as myself. After months of asking around someone told me that this is a sign of a hot water tank going bad. Do you know if it's true? I have spent money already with my own ideas. If this is the problem I will gladly go out tomorow and purchase a new one. Any information you can give me will be greatly appreciated.

A: First off, this problem doesn't mean your water heater is going bad. You're experiencing water hammer. You open the tap and water flows. When you close the tap, the water is still moving in the pipe and when it stops, it does so with a jolt. Have someone check the water pressure at a time when the tank isn't firing. It should be about 50 psi. If it's significantly higher than that, have someone install a pressure reducer. If you find the pressure is above 80 psi, send us another e-message. There will be another problem that will have to be addressed. (1995-2000)