I looking to control the water pressure (actually mean flow) in my house. When the irrigation for the back yard turns on it uses a significant amount of water. So much so that the water inside the house lowers to almost a trickle. What I am looking to do is install a ball valve between the main water line and the irrigation line, the ball valve would open or close depending on the pressure on the house side of a check valve. The pressure reading will be taken after the check valve on the house water line. I'm thinking once the water pressure drops below a certain psi on the house side of the check valve the ball valve starts to close, once the water pressure reaches certain psi on the house side of the check valve the ball valve stops closing, and when the pressure is above certain psi on the house side of the check valve the ball valve continues to open and stops at it's max open. I suppose depending on how smart the valve is, i might need to find a way to stop sending a signal to the valve when it is fully open or close as to prevent any damage to the valve motor.
I am looking a valves similar to these: ( I would like to avoid solenoid valves as I want the water control to be gradual)
Check valve similar to this:
https://www.rona.ca/en/product/burcam-lead-free-brass-3-4-inch-check-valve-750760-0668016
I haven't looked into pressure sensors yet however, it will need to fit onto a 3/4" water line.
I have a Pi5 lying around that I could use assuming that would be the best route.
Looking for advice or potential routes I could take.
Thanks in advance.
It may be illegal to bypass the check valve, that is usually required to prevent backflow from your house water system into the water main when the pressure drops in the main water line.
Is there a pressure regulator between the water main and your house water system? That may have a limit to how much water it can flow, or contain a filter that is partially restricted.
What material are your water pipes made of? Not unusually for a really old iron pipe system to rust internally and restrict the flow.
The goal is to allow full flow to the irrigation but when the house needs more water the valve closes.
I understand your dilemma. But you probably do not have a pressure problem unless something has changed in your water supply, be it municipal or well. Most likely you have a volume problem.
If your house runs low on water when the irrigation is on and you start to close the auto valve so your house has plenty of water flow (volume), you will run the chance of not having enough water to the irrigation system.
You might need to investigate increasing the number of zones and having fewer heads per zone, thus reducing the water demand on the irrigation system at any given time that it is running, thus increasing the amount of water flow to the house.
And your backflow preventer is in the wrong spot. Where you have it in the drawing could still allow dirty water to flow in to the house water line. It needs to be on the irrigation line, not a lateral but the main line.
I'm not looking to bypass a check valve, I have the water line branching from the main which has a check valve before the main water valve.
There is no issue with the pressure regulator, I am getting around 12L/min when the irrigation line is open.
The water lines that are feeding the house are copper, and all brand new pex after the main water valve. No concern with particulate plugging anything.
How much flow do the heads on a particular zone require? You may have more sprinkler than supply. Or be pushing the limit anyway.
I "somewhat" have a volume problem but its not new. What I see is that I am trying to pull more water from the main than the system can supply.
Im not concerned with starving the irrigation system. The drop in flow to the irrigation system would be only for a couple min or so. I am looking to keep the water pressure at a "normal" pressure in the house while the irrigation is on without adding a booster pump.
I would love to add more zones to the irrigation system however, that will cost significantly more than a few valves, pressure sensor, and controller. Plus it would take a lot more physical effort to install the additional zones.
I have not shown my whole water system, there are check valves in the correct spot to prevent dirty water from getting into the house. I was only showing what I was wanting to add to achieve the goal I am looking for.
Oh I know I am pushing the limit but I am not overly interested in adding additional sprinklers and zones to reduce the draw of water. looking to divert the flow to the house when needed and back to the irrigation when the house doesn't need it.
Branch off the water line, before the house pressure regulator, and install a 2nd pressure regulator for the irrigation system (or run full pressure if that is acceptable). The only need for a ball valve would be as a cutoff, which you should have anyway.
Beware of creating positive feedback in your system which will create oscillation in the valving.
Well in that case, if your not concerned with the irriagtion system being starved for water (the heads won't spray as far as the system is designed to), then the easy thing to do would be to do as LarryD suggested in post# 2.
But if you are looking for a cool arduino project, I totally understand that as well. I did not look at the valves you showed. Are they servo controlled?
That seems like an easier solution than automating it. I still worry that if both the irrigation is on and the house try's to draw water the flow will still be quite low to the house.
If the water main restricts the flow to your water line, then there is nothing you can do.
A new pressure valve in the irrigation side might work, but be aware that if you drop the pressure to low the heads will not even pop up. I am not sure what you are working with but generally they do have a minimum required pressure.
That for sure is a concern, I would think ensuring the valve closes and opens slowly there will be minimal oscillations. Somewhere between 4-10 seconds to fully open or fully close.
Except more zones with fewer heads. Depending on the water main itself, of course.
Other than restricting flow to the irrigation when the house needs water then allowing the flow back to the irrigation when the house doesn't need it.
What are you going to do when the irrigation schedule conflicts with needing to run the dishwasher, the washing machine, and you need a shower at the same time? The irrigation will get zero water. unless it runs in the middle of the night or when noone is home.
For the most part the irrigation could starve for a couple days and the yard will be fine lol. Water pressure/flow to the house is more important. I have the irrigation scheduled to run when the sun is down.
