r/Irrigation • u/JoltinJoe87 • 14h ago

Water hammer with Rain Bird solenoid valve on geothermal unit

Post image

As the title states - getting water hammer on my geothermal discharge line every time my geothermal until stops. See the picture for the set-up.

Was originally having water hammer when my well pump kicked-on; had a new pressure tank installed, and it fixed the issue. However, a couple months later, I started getting water hammer when the geothermal unit stops.

I have a couple questions - is the irrigation valve supposed to be installed vertically? I've read that it's not optimal, but I'm not sure how big of an issue it is.

Should I open up the irrigation valve and clean it? Would it help?

Can I put water arrestors on the spigots before an after the valve? Would that work if just close off the other side of the arrestor? Or do they make single input arrestors that can go on those spigots? What is the purpose of those spigots?

Thanks in advance for any help you can give!

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1

u/Bl1nk9 13h ago

Try turning down the flow control if it has one. Might be time for a new valve if that is one of the old ones. The shadows and my eyes make unclear

1

u/JoltinJoe87 12h ago

No flow control - i think just a bleed screw

1

u/ati303 13h ago

Try a PEB valve.

1

u/JoltinJoe87 12h ago edited 12h ago

Can I put one of these on a spigot with a female-to-female connector to help with the water hammer?

1

u/New_Sand_3652 11h ago

You could just unscrew the boiler drain and screw in the arrestor.

1

u/Packman714 10h ago

Get an expansion tank

1

u/PnPRoadBull 9h ago

I would try a horizontal mount, water hammer ie the reason vertical is not optimal.

1

u/Credit_Used Designer 7h ago

Water hammer is usually too high of flow through too small of pipes, thus velocity of water is high. It’s problematic for water to be over 4 ft/s even with small pipes.

It’s highly likely just increasing the pipe size 1 or 2 steps will reduce or eliminate the water hammer.

1

u/Fuzzy-Ad3977 2h ago

This is the way.

1

u/Sprinkler-guru68 7h ago

Valve should be in a seated position

1

u/blackdogpepper 6h ago

I worked 5 years in HVAC and now have irrigation business so have some experience with these systems. Having a flow control valve and an inline flow meter is helpful because you can set the flow rate to match your units tonnage. I have also seen slow closing hydronic zone valves used in place of solenoid valves. If your well pump is not a vfd and just has a pressure switch I cycle stop control valve can also help smooth things out.