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I have 8 Weathermatic Silver Bullet Valves.

I have 8 stations in my sprinkler system. Never had any thumping until I had to turn house water off recently.

Now when the sprinkler system is turned on severe thumping in my house.

I had to turn sprinklers off this morning because thumping is so loud bothersome.

So I tried what the web suggested I removed sprinkler heads from station 1,2,3 and ran water through those stations for about 5 minutes or so. Shut off the stations and attached sprinkler heads, and tried to water, no luck, still thumping.

I manually opened all 8 valves and let them run for a while to remove air, still thumping.

This is driving my nuts. How do I fix this??????
When I need to turn the house water off I can not have the sprinkler system thumping.


The sprinkler system is on it's own dedicated hard water line bypassing the house water.
The house water line splits, one to the house through the water softener, and then the hard water to the sprinkler system.


The hard water line has two outside faucets.
I opened those up and did get some air removed.


The sprinkler system line also has a on/off ball valve that allows me to turn water off to all the sprinklers.


This driving me nuts. How do I fix this so it goes away and stays away.


How do I get air out of system and stop this thumping and stop it from happening again.


Any help is greatly appreciated.


I have spent a lot of time trying to fix this.


Thank you

Water turned off to house for hot water heater issue.
When water was turned back on no issue with house just the sprinkler system hard water line.

The hard water line is a dedicated line to sprinkler only bypasses house soft water.

Pressure valve on main line that controls both house and hard water line.

I bleed all the valves, removed sprinkler heads, flushed with water.

Thumping only occurs in 5 of 8 valves, 3 are quiet.

Have spent a lot of time messing with this because it is really annoying.

Next I will try shutting off water to all sprinkler heads, manually opening all valves, and let it sit for few hours to see if that removes air from lines.

I can not have this happen every time I need to turn service water off to house.

I do not understand why I can not get air of lines.

It has worked perfectly before shutting the water off.

What else can I do????

So I tested water pressure and the sprinkler hard water line is 110 psi. So that explains when I turned on a faucet on the hard water line the thumping stopped, and when I turned if off, thumping started. Clearly pressure in line was causing big thumping noises in pipes. I had thought the Weathermatic Silver Bullet flow wheels would have helped fix this.

I don't understand how turning off house water, and then turning it back on created this thumping noises. It was not thumping until I turned off the house water.


Anyway, I installed a pressure valve in the hard water line to 65 psi, and the thumping was greatly improved, not all gone, but improved.

Was this thumping air in pipes or water hammer?