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Alang
Jul 27, 2010, 11:15 AM
Every time we turn on the hot water tap we hear a loud banging sound how can we fix this problem?

speedball1
Jul 27, 2010, 11:33 AM
Would this be a gas or electric water heater? I'm betting on gas. Do I win my bet? Back to you, Tom

Alang
Jul 29, 2010, 10:44 PM
Sorry it is an electric geyser, what do you suggest?

massplumber2008
Jul 30, 2010, 09:53 AM
Alang...

Does this noise happen with one specific tap or all hot water taps? Let us know...

Mark

Alang
Jul 30, 2010, 11:52 PM
Yes this happens with all of th taps

Thx

Alan

massplumber2008
Jul 31, 2010, 04:02 AM
Hi Alan:

OK... more questions then.

Has this always happened with the hot water taps or is this new?

Do you have an expansion tank or something similar at the water heater (see image)?

Finally, do you have an water hammer arrestors in your house (see image)? You might also find tall pipes sticking up at say the washing machine... these would also be considered water hammer arrestors...

Let us know. Getting closer to an answer... I hope!

Mark

speedball1
Jul 31, 2010, 10:36 AM
\Mark had the right idea when he mentioned water hammer.
Back in the 60's we were required to to put air chambers on all bath lavatories and kitchen sinks. Over time water and condensate built up in them and they must be recharged. First turn off the house at the main house shut off valve. Then open hot and cold faucets at the farthest bathroom to prevent air lock.(This is important.) You will find under each fixture little brass or chrome valves. These are called angle stops. With a small pail held under the angle stop to catch the run off look under the handle of the stop and you will see a nut with the stem running through it. This is called the bonnet packing nut. Put your wrench on it and back it off counterclockwise. Now open the stop and remove the stem and washer assembly, The stop will began to drain. When it has quit draining reassemble the stop and move on to the next one. Do this on each one of your angle stops. There will be six of them in a two bath home. When you are done, close off the faucets you have opened, turn on the water to the house, and give yourself a pat on the back.
You have just recharged your air chambers and saved yourself a hefty service call bill. Hope this helps you out and thank you for rating my reply. TOM