# Slow start to zone pressure



## whereswendel (Oct 8, 2020)

I have an irrigation system that has 5 zones. Four of the zones work correctly. 1 zone has been acting odd.

When the odd zone is turned on it initially dribbles out water at each sprinkler. It takes about 75 seconds for the zone to get up to speed and is pushing water out at the desired pressure. For most of the first minute it is sending an arc of water at each sprinkler to about 2-3 feet. Once it is fully pressurized each sprinkler is sending the water about 30 feet.

There are 5 sprinklers (Orbit Saturn 3 or 4) and 1 Rainbird 4 inch, 4 ft radius, 90 degree. The pipe is PVC schedule 40 3/4 inch. The valve is an anti-siphon brass valve. I've changed the washers. When I unscrewed the Solenoid it popped at with some velocity. I then screwed it back in. [Previous to unscrewing, it would not fully pressurize].

One other thing to note here - is that the value is not cranked all the way counterclockwise. I've had to find a position that sends the water the furthest.

I suspect the valve may need to be replaced but I'm wondering if I am overlooking anything. There are no visible signs of broken pipes / leaking.

Does anyone have suggestions about what may be wrong?


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## GrassOnTheHills (Jul 3, 2020)

First off, it's odd that you have different heads with (based on what I think I'm reading) different radius on the same zone.

That said, I have a similar problem but it doesn't take 75 seconds to load up the zone, more like 15. In my case I think it's just that I designed the zone to be too close to the available pressure and so it's just a slightly low pressure situation (I have 14 spray heads on the same zone that has a 150' mainline run with another 70+' lateral run on just 62PSI).

Your situation very well may be pressure related.. does your valve have flow control? Has the zone always acted like this or did it start suddenly?


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