“Water Hammer” is a term used to describe a loud banging in your plumbing system pipes after a valve is shut off. This phenomenon is often caused by a large build up of rust or minerals inside a shut off valve. It can also be caused by damaged or worn washers inside your faucet.
Following are the steps one should take to fix the water hammer problem. The first thing you should do is to locate the water main valve. It is important that all water supply to your home is shut off in this first step. So, if you are, perhaps, only hearing the banging noise associated with one shut off valve, don’t try to shortcut the process by just shutting off water for that fixture. Take the time, if you have not done so previously, to locate the main water valve; it is often located outside the home, often in your front or back yard. Turn that valve off completely.
Next, go through your entire home and open all the cold water faucets. Make sure you include all sinks, bathtubs and showers. If you live in a multi-story home, work from the top down. For example, start with all the cold water faucets on the 2nd floor, then move to the 1st floor, then on to your basement.
Once you have opened all the cold water faucets, you are going to want to wait for all the water to drain from them that had been stored up in the pipes of your home. This will probably take approximately twenty to thirty minutes. Check all the cold water faucets you had opened to make sure they have all completed the draining process. Now, flush all the toilets in your house.
Okay, now you are going to want to go back to the main water valve for your home and turn it all the way on. A good flushing of all the pipes is important, so allow enough time for a good, steady stream to come out of all the fixtures. Yes, this is going to take a bit of time, as you will want to back and check all the sinks, bathtubs and showers to see that a steady stream is coming out for each. Overall, the faucets for each fixture should be allowed to flow for ten minutes each.
Now, you are going to go in reverse. That is, begin turning all the cold water valves off, starting from the lowest and moving to the highest. Once the main water valve had been turned back on, your toilets should have refilled, so they should be fine. Likewise, as all the water pipes in your home should now be refilled, your washing machine should be good to go too.
There is a quick way to check if this procedure has fixed the problem. Simply flush the toilets and listen for the “water hammer” banging noise. Hopefully, this do-it-yourself plumbing technique will have eliminated the water hammer noise. However, it may not work 100% of the time. At this point, it would be recommended that you call a plumber to zero in on the problem. It could be damaged or worn washers in the valves, or other issues.
Charlie Teschner started MESA Plumbing, Heating, and Cooling in 1982. Charlie has a journeyman and master plumber’s license. He was raised with a strong work ethic and he now applies those values to tasks such as Longmont, CO heating repair.