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1

Sunday, March 11th 2018, 5:02pm

Zone 4 no pressure

So a few months back I lost pressure in one zone. Called my normal contractor (company A) and he said the well probably cavitated and I’ll need a new one. ANNNNNNDD, I got a second opinion. Different company (company B) put new (low pressure/output) heads on the entire zone. Well it still doesn’t work (it’s a long story and I won’t be calling them back). 3 zones work fine, aside from being a little slow to pressurize. Well I noticed this giant crack in the pipe leading from the index valve. Why no one noticed this is beyond me. Anyway, I fixed it and it still has no pressure. What are the potential causes?

Other broken pipes?
Cavitated well?
Bad index valve?

Others?

Wet_Boots

Supreme Member

Posts: 5,279

Location: Metro NYC

2

Thursday, March 15th 2018, 10:16am

Try to evaluate the well on its own, just as a water source, and not what drives a sprinkler system. If you have to add some shut-off valves and outlet tees, consider it the cost of being able to know what you have, instead of having to guess at it.

This advice comes from the word "cavitated" that you posted, which suggests that the water source may have changed in some way. Water tables can drop lower, to a point where it is beyond the ability of a pump to bring water to the surface, at least in the same quantity and pressure as was done originally. Another change that affects pump output is a well point screen becoming clogged, with similar effects on pump output.

3

Wednesday, March 21st 2018, 4:33am

Try to evaluate the well on its own, just as a water source, and not what drives a sprinkler system. If you have to add some shut-off valves and outlet tees, consider it the cost of being able to know what you have, instead of having to guess at it.

This advice comes from the word "cavitated" that you posted, which suggests that the water source may have changed in some way. Water tables can drop lower, to a point where it is beyond the ability of a pump to bring water to the surface, at least in the same quantity and pressure as was done originally. Another change that affects pump output is a well point screen becoming clogged, with similar effects on pump output.



All of the other zones work fine though. And we’d had plenty of rain, so the water table is currently high. Even years back when we had a drought they all worked. Does that make a difference?

4

Wednesday, March 21st 2018, 4:35am

Also, I have an in-line spigot which flows plenty of water.

Wet_Boots

Supreme Member

Posts: 5,279

Location: Metro NYC

5

Wednesday, March 21st 2018, 7:09am

You still do not know what the actual performance of the well is. That means you are playing guessing games, as it appears from this side of the internet. What pressure readings do you have on each zone? You do have a pressure gauge, don't you?

Consider capping off heads in the low-pressure zone, one at a time.

Index valves are almost unknown outside of Florida, so there won't be a great deal of advice on them from elsewhere. I can affirm they can be taken apart and put back together without much bother.

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