Siphon won't break on pressurized system, discharge going one floor below

I cant get my irrigation setup to break the siphon.

The system is as follows... foot valve > 1" pvc suction pipe > Leader 1/2hp pump > 30' of discharge pipe travels one floor below > manifold feeds (3) tables, each table has a pressure relief valve at the end of each loop. Room has 144 sites with (2) 0.5gph emitters.

I believe the drop of the feed pipe going to my tables one floor below has created enough siphon to keep my foot valve open. I realized this morning when my res dropped over 100 gallons overnight. It's a real slow siphon.

I thought it could be coming out of my pressure relief valves, three of them in the room, but I closed the shut-off valve just before each relief valve and my water level in the res still dropping very slowly. Is it possible that there is enough pressure from the 10' drop in elevation of the discharge pipe that water could be coming out of my PC emitters? Either that or there is a leak somewhere in the system.

Anyways, I really don't want to install a solenoid on the discharge line. Any other options?

If you “T” in a one way check valve like this it’ll break the siphon


@Sk-one may have some insight on this possibly?

Can u put a hole a few inches down the main feed line and fit a 90 deg elbow in said hole………then point the other end directly back into your rez…….that way when your feeders kick on water flows threw elbow and back into your rez…………when it shuts off……that elbow will “breath” and break the siphon……..ran into this on my set up……I use a 55 gal rez and do the same thing……workes like a charm

I uses a tiny little 1/8th inch elbow for a feed line…..

This…… will…… work….. for….. you……

bk78 said:

This…… will…… work….. for….. you……

https://www.amazon.ca/American-Valve-P32S-1-Socket-Schedule/dp/B004NHM4EG/ref=mp_s_a_1_2?adgrpid=66793655691&gclid=CjwKCAjwiY6MBhBqEiwARFSCPlnGWWQimGmpRUIhxxbpdu0-2O0WcS_3fd4WSONSuu88FV4Ydy5XxRoCKLcQAvD_BwE&hvadid=310039093162&hvdev=m&hvlocphy=9001389&hvnetw=g&hvqmt=e&hvrand=10125052528406133553&hvtargid=kwd-299106009593&hydadcr=28129_10626383&keywords=1+inch+pvc+check+valve&qid=1636073706&sr=8-2

Click to expand...

I was thinking of adding a check valve somewhere on the discharge line but would it really work? The foot valve at the start of my suction line in the res is pretty much a check valve too? I'm convinced the pipe diameter coupled with the a 10' sharp drop in elevation has enough "pull" to keep the foot valve open... I wonder if adding a second check valve will lessen the "pull" enough to keep the foot valve closed.

2klude said:

I was thinking of adding a check valve somewhere on the discharge line but would it really work? The foot valve at the start of my suction line in the res is pretty much a check valve too? I'm convinced the pipe diameter coupled with the a 10' sharp drop in elevation has enough "pull" to keep the foot valve open... I wonder if adding a second check valve will lessen the "pull" enough to keep the foot valve closed.

Click to expand...

I'm not sure of your exact setup, but if it's similar to this video, a check valve would work for you.

Ended up using a "sure vent" on my discharge line... problem solved. Thanks for all the suggestions everyone.