# Can I measure water pressure at valve solenoid hole?



## BigMike (Jun 6, 2020)

My question is:

Can I unscrew Jar top solenoid and retrofit a water pressure meter (Hose bib size)by adapters to see if my valve is getting adequate water pressure by measuring at the solenoid port? I know the solenoid port has only a tiny hole feeding it water as a bypass but water is PSI and my "I" will be tiny I think it should still build up the same pressure. Will I get an accurate measurement on my water pressure meter? My outside water bib is showing ~52 PSI so house has adequate pressure and other sprinkler zones are working fine... is it worth trying?

Thanks in advance.


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## hsvtoolfool (Jul 23, 2018)

BigMike said:


> Will I get an accurate measurement on my water pressure meter?


Through a tiny port hole? I doubt it, but it's an interesting experiment. Please take photos if you try it so we can see what you did.

I added a 1" ball valve hose bib at the end of my manifold for this reason. I use it to flush the system, winterize, and measure flow/pressure right at the valves. Going from the meter, I have a 100 mesh screen, followed by a Reduced Pressure Zone Device (RPZD backflow preventer), followed by a Pressure Reducing Valve (PRV), and finally the valve manifold itself. I thought it would be nice to measure the pressure and flow right at the manifold after all that congestion so the PRV could be adjusted accurately.


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## BigMike (Jun 6, 2020)

This was an easy experiment I did at my garden hose before I search for the fittings to adapt the solenoid hole to water hose size. I barely turned on the water to a very very low trickle level like the flow of water that comes out the solenoid hole. Then connected my pressure gauge at this flow level. It slowly pressurized to around 45lbs PSI which is what I normally get from the end of this 150ft garden hose.

Based on this, I am confident that I will get the same results connected to the solenoid hole. So, this will tell me the pressure making it's way into the valve when it is off. Also, based on this finding It wouldn't tell if the main line was pinched/crimped unless it cuts the water completely off since a tiny bit of water coming through will still show the pressure. If the main line had a break, I would tell by the water meter always showing some flow.

I guess there are two factors to take into account, The pressure and the flow volume. We can measure the pressure but the flow volume is harder to tell unless the line is opened and measured for GPM. In the case of my sprinkler zone having very low flow coming out of the heads, I can only keep looking for the broken line that is underground so I can repair them and hope it fixes my issue.

I'm getting to the point of hiring a professional! This is testing my patience.

If I'm crazy, let me know because I've never had to dig deep into irrigation work.... It just always worked except replacing the popups here and there.


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## hsvtoolfool (Jul 23, 2018)

BigMike said:


> In the case of my sprinkler zone having very low flow coming out of the heads, I can only keep looking for the broken line that is underground so I can repair them and hope it fixes my issue.


Oh! I missed that you were debugging a zone. Have you tried a a pressure gauge out at the heads? You'll have to find the right brand gauge for your heads.

Has the zone worked correctly in the past? I'm not sure how to find a secondary line break except looking for a bubbling spring of water.


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## BigMike (Jun 6, 2020)

Sorry, I didn't mention the reason I'm doing this. I started a thread over the weekend about 2 of my zones having low output. MrMister suggested capping/turning off all heads and looking for water bubbling up. I found a leak and fixed it but still have low output. Either there are more leaks or something else going on.

The Solenoid hole pressure test just entered my curious mind and thought I'd ask if it's feasible.

This zone worked fine last year. The problem I have is there was a pool added after the sprinkler system was put in so all valves and horizontal lines are buried extra deep due to grade being raised for the pool at this zone..... This zone has things about 3ft deep and all scattered throughout the yard, not in one common place. I really like the Manifold design with all valves in a central location like I see on this forum and utube.

.


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## g-man (Jun 15, 2017)

Measure pressure is like measuring voltage. It only gives you the potential to move electricity thru a resistance. It seems that your issue is flow (current in the electrical analogy). Either you have a leak or a kinked hose in that zone.


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## BigMike (Jun 6, 2020)

I adapted the pressure meter to fit the top of a sprinkler riser and I have 0 psi pressure measured there. I let the water run and found the flow to be about 20 GPM on bad zone and checked the flow on a normal good working zone to be around half (10 GPM).

I found the GPM measurements from watching the street water meter.

After it ran for about 10 minutes I found another flow of water making it's way into the back alley adjacent to this zone.....

Time to dig again.


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