Do You Really Need a Pressure Regulator? Understanding Water Pressure & Irrigation Systems 

You too, thank you again for all your efforts, you're going to have an amazing garden!

I want to put a drip system on a sprinkler line…. What do I need to put on the li e after I take the sprinkler head off.

Jaimie, here's a video that walks through the process of adding a drip system to a sprinkler line. The video description includes a parts list with the parts you'll need: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-l8gzTCgZQLQ.htmlsi=JhsVQsxFeOhpw6z8 Please don't hesitate to send any follow-up questions this way here in the comments or via our website!

You're very welcome, I hope the video helped! If you have any questions left about pressure regulators, just say the word, happy to help :)

We do actually see folks do exactly that! Lowering pressure that way is not entirely uncommon :) Normally it's not recommended due to it being difficult to tell when you're at an appropriate pressure level, but using a pressure gauge eliminates that concern to a degree. There will be some extra wear and tear on the valve going that route, but they tend to be built sturdy in order to handle the static pressure anyway. So while not necessarily ideal, it's definitely possible.

You bet, happy to help! On the water shooting out of the regulator, that part is normal -- regulators don't regulate downstream pressure unless the lines are pressurized and emitters are flowing. When the line is disconnected, there's no pressurization, just flow, so they won't regulate (that's the reason you can't hook a gauge up directly to a regulator -- then you have pressurization but now flow). For the water gushing out all the beds, was that water coming from the drip tape itself? If so, let me know, I have some ideas (and some solutions). If you prefer, you can reach out at this Contact Us link -- it sends us an email. If you put Attn: Adam, or "from RU-vid" I'll know and get back to you promptly (also happy to help you here if you prefer as well) :) Here is that link: help.dripdepot.com/support/tickets/new I look forward to assisting!

Great question! In most gravity systems, the pressure regulator is going to need to be downstream a bit from the water source, as there is typically not enough pressure to engage the regulator right at the source. With the common pressure regulators, you need at least 5 PSI more at the inlet than what they regulate to downstream. This means if you were using a 15 PSI pressure regulator, it would need to be placed in a location that has at least 20 PSI at the inlet of the regulator.

Great question! Gate valves (and even other types of valves) can work, but regulators have the advantage in that they do compensate for inlet pressure. Across a fairly wide range of pressures too -- the most common one for residential users is the hose threaded 25 PSI version which can maintain 25 PSI downstream pressure anywhere from 30 to 105 PSI at flow rates of 0.5 to 7 GPM. They have larger ones for different applications and, save for their Limit Valve, work essentially the same. If inlet pressure never fluctuates a valve could probably serve just as well, but I'd likely still recommend the regulator as they tend to cost significantly less but accomplish the job just as well :) Senninger, a manufacturer of pressure regulators, wrote a white paper that covers them pretty well if you (or anyone reading this comment!) wanted to dive in a bit more: www.senninger.com/sites/senninger.hunterindustries.com/files/understanding-pressure-regulation-white-paper.pdf Edit: Apologies, I didn't address the plants with different harvest times! In most cases an inline shut-off valve to shut that portion of the irrigation would do the trick -- since most drip irrigation works around the same pressure (10 to 30 PSI, with the most common being 25 PSI) different pressure is not usually needed for different emitters. The big exception is drip tape, which has to be 15 PSI or less (depending on wall thickness), but most other emitters will work fine at 10 to 15 PSI, so even in those situations pressure could be maintained at 10-15 even after shutting portions of the system down for the season.

Depending on the size of your lines, it's very possible something could achieve a sort of quick disconnect so you can easily remove lines -- is it the drip line themselves or the mainline feeding it you'd like to be able to quickly disconnect? For 1/2" mainlines, we see a lot of folks use two fittings to create a sort of quick disconnect -- one is a male threads x tubing and the other a female thread swivel x tubing -- the swivel on the female thread fitting allows it to be turned without needing to turn the entire thing, so you can quickly unthread it to disconnect the lines. The same is possible for 3/4" and 1" mains as well. Here's a link to the 1/2" versions just in case (the larger ones are available there using the dropdowns) -- Male threads: www.dripdepot.com/search?q=1203 -- Female threads: www.dripdepot.com/search?q=1193

104 PSI is definitely likely the culprit! That's some very high pressure -- a good problem to have sometimes, you'll always at least have enough available pressure for pretty much any emitter type (heck, you might need to regulate even for lawn/turf sprinklers at 104) :)

@dripdepot Thanks for that quick response! I should have mentioned that the 104 was my static pressure. I will take additional pressure readings this afternoon. I should take a reading after the backflow preventer since it reduces the pressure by 15 psi according to its manual and another reading with the system running.

@@harvey8695 You've got the right of it, the backflow will definitely cause some pressure drop, and friction loss while water is flowing some more. If any questions come up while you do this (or after depending on the results!), don't hesitate to comment, happy to assist :)

@@dripdepot the dynamic pressure dropped to 65 when the system was running, much better than the 104 :)

@@harvey8695 Ah, very nice! Is this for a lawn system? If so, you're looking good unless using unregulated spray bodies (which are somewhat rare now). Great for rotors and regulated spray bodies, great how it came down to basically sweet spot =D

If you have any questions on any of it, I'd be more than happy to help -- and I hope your headache is gone this morning! :)

Most likely you'll go 15 to 25 PSI -- most drip emitters out there will list emission rates at various pressures (for example, 0.40 GPH at 15 PSI, 0.50 GPH at 25 PSI, etc). You can use those specifications to select a pressure regulator. 25 PSI is a great level for the vast majority of drip emitters and is where most folks operate at. The big exception is if you use drip tape, the thin walls on drip tape prefer 10-15 PSI depending on the wall thickness of the tape.

You got it Marjorie -- in the setup you described, you'd want it after the timer -- this is because regulators (and pretty much all the head assembly parts except the timer) are not rated for constant pressure, so they have to come after any timers or valves so they're relieved of pressure when the system is not in use. Most garden hoses aren't rated for constant pressure either, I'd double check that yours is so you don't get another broken line leading out to the garden :)

@@dripdepot This is really helpful. So would you suggest TWO pressure regulators? One where the hose comes from the house and one at the end of the hose, where the timer will go (after the timer)? Thanks so much.

​@@MarjorieGeiser You should be good to go with one regulator :) There are situations in which to use two, usually just when the inlet pressure is so high you want to reduce it from an incredibly high pressure (120+ PSI) down to something more common (50-60 PSI) before it hits the drip system where you regulate it down to 25 PSI. Basically, only when the pressure is so high it exceeds the maximum pressure of the 25 PSI regulator, but pressure that high is pretty rare in residential applications, you're likely well within the norm on faucet pressure :)

That's a very good question, you're definitely headed in the right direction with your query. There's a couple things at play here: the regulators we're using in the video cannot withstand constant pressure, so you generally need one for each zone or line (however, if you open them all up at once, you could go with just one so long as it is relieved of pressure when the system is not in use). With that said, there are pressure regulators that can withstand static pressure (these here: www.dripdepot.com/search?q=14405 ) and can be used upstream of valves so that they can regulate for multiple zones/lines. With that also said, there's another limitation you might run up against when trying to operate many lines/zones at the same time: flow rate. In addition to sufficient pressure, you'll need sufficient flow for all the emitters operating at one time. As a quick example, if your water source flows at 10 GPM but you have 15 GPM in emitters trying to run, some of the emitters will be starved of water and won't work as they should, if at all. The symptoms for lack of flow are very similar to that of insufficient pressure: not emitting as much was as they should, dribbling instead of spraying, barely dripping, etc. Depending on what your water source is, there's an easy and reasonably accurate flow rate test you can do with just a timer and a bucket. Time how long it takes to fill the bucket with water and then plug the numbers (volume of bucket and time it took to fill) into this calculator, it will give you a pretty good approximation of your water source's flow rate: www.dripdepot.com/irrigation-calculators/flow-rate-calculator You can then compare that to the flow rate of your emitters to see how many can operate at once. If you're not sure of their flow rate, see if you can locate their specification sheet online, they'll generally list their flow rates at various pressure levels (e.g., 4.0 GPH @ 25 PSI, etc). :)

@@dripdepot thanks for the fast reply and taking the time to share ideas and options. I have a much better understanding now. I have another question on the Mazzei injector, there's a low flow and high flow, do i get the low flow for drip tape?

​@@ClearWater7.62 That can depend -- you are right that drip tape is low flow, however that's "per emitter." If you have thousands of emitters operating at once, even a drip tape system could have a lot of flow and qualify for the high flow model. Your instincts are right though, as there's a good chance that even with all 8 lines running you'd still be low flow unless your 8 lines are very long. If you end up running less than all 8 at once, you'd almost certainly be in the low flow side of things (again, unless they're extraordinarily long).

@@dripdepot thanks for the input. I went ahead and ordered the prlv and Mazzei injector on your site. If anything at all, I'll just have to split 8 lines in two separate irrigation time.

@@ClearWater7.62 You're very welcome, any time! If you have any questions after everything arrives, don't hesitate for a second to reach out here or our site, we'll be happy to help :)

A plumber will have better odds than one of the big box stores, but this may be something I can help with :) Are you going to be running the irrigation system from a hose bib, or are you going with a sub-surface system fed by solenoid valves? This will determine what thread type (hose vs pipe) you'll want. The flow rate of the system will determine which model (high flow, low flow, medium flow) would best serve the system. The flow rate of your irrigation system can be determined by adding up all the emitters that will be operating at once. For example, 500 0.5 GPH drippers will be a system flow rate of 250 GPH. Happy to help with any follow-up questions, don't hesitate to drop a line!

@@dripdepot Hi! Thank you!! Apologizing ahead of time for this long message. Okay. More background info. In the area where I'm trying to prepare all of this I used to have a lawn. That lawn has been gone for years. The sprinkler system is still there. My dad and I started to convert the system to a drip irrigation system. He added a second non-siphon valve, which I think was what you were mentioning - ...?, he put in about 3 risers, two of which have (I think they're called) posts for the drip lines. The water supply comes from the backyard hose bib. All of this is in my backyard. The sprinkler system was put in about 17 years ago, and my dad and I checked the lines then in 2021 and replaced two of the PVC pipes that were leaking. All the pipes are (think they are called) 40 standard PVC. These modifications, my dad and I, started in 2021. He passed later that year so we weren't able to finish it. Now I'm trying to complete this or hire someone. I think, after the estimates, I'd prefer to try to complete this myself. One estimator told me after an initial PVC repair that is evident that they would run water through the lines multiple times to make sure no leaks, and they would repair any leaks and replace any pipes that need to be replaced. He'd use my existing timer. We talked about the main water valve and said that it has a high pressure reading, above 60, and needs a pressure regulator. Second estimator said I needed a backflow preventer and pressure regulator and he could set up on a new PVC line from the backyard spigot (with a ball meter shut off valve there - I think that's what he called it) in my backyard versus going from the main valve water line in my front yard. The last estimator said I need a whole new system since it was so old. Replacing all the PVC pipes, new timer, "vacuum breaker", not a pressure regulator, at the main water valve in my front yard going back to my backyard. My brain is a little overwhelmed 🤯. I hope with all this info I have answered your questions. Thanks again!

@@dripdepot one more thing. I have 8 sprinkler heads, 3 of which have the risers. I didn't need all of the heads to have risers yet since I'm going to start with a small garden to start before adding the risers to the other sprinkler heads. Basically converting those from sprinkler heads to risers. Hope this all makes sense.

@@jonesy5722 Perfect on the information, thank you for sending that over! This should be enough to really dive in -- I'll reply with everything on your other comment as soon as I've worked through it all. With the information you sent over, I do think you can DIY this without too much trouble -- I've also seen the recent quotes to have something like this professionally done and I suspect that even if the project takes you awhile, you'll come out well ahead DIY'ing :) I'll be in touch!

@@jonesy5722 Ok, let's see how much of the existing system you might need to make use of for the drip system -- this might end up being very straight forward depending on the size of the drip system. How many raised beds do you need to irrigate, and what are their dimensions? I suspect you might be able to run the entire thing off of one of the risers that already exist -- If not, it would also be pretty easy to run it from the second non-siphon valve you have. Pressure regulation will be easy and inexpensive either way. You mention that the water supply comes from a backyard hose bib -- does the hose bib lead to the valves, or do the valves feed the hose bib? No problem either way, I'm narrowing things down for the easiest (without losing any effectiveness) DIY route. The estimator was right about checking for leaks, but this is something you can easily do -- run water through the system and find any locations that are leaking -- to detect leaking, you can listen for it (hissing for smaller leaks, gurgling for larger) and watch for wetted ground in places it shouldn't be. Fixing it is fairly straight forward, typically you just cut the damaged portion out and then re-connect the line with a coupling. I can help find the parts here. Here are the options for getting the raised beds irrigated that I see so far from your description: Valve: -- At the valve outlet, you'd connect a filter and a pressure regulator, then an adapter so you could connect your mainline tubing. If there is already PVC pipe on this valve, it would be Filter --> Regulator --> PVC Adapter to connect the existing pipe (again, all things I can help you find, and all reasonably inexpensive). This could easily be controlled by your existing controller, as it sounds like you might already have one. Hose Bibb -- If any of the valves are feeding the hose bib (or it has a different supply), a drip system could also easily be connected to it. This is probably the easiest route, but may not be able to take advantage of your existing controller/timer. You wouldn't even need to go PVC pipe here (unless it's already present, then may as well use it), you could go straight to poly tubing and run it over to the beds if it's within reasonable distance. Riser: If one of your risers is fairly close to the raised beds, a single adapter can turn it to hose threads so you can connect Filter --> Regulator --> Adapter for Tubing. Assuming the riser is in one of the zones with one of the valves, it could also be ran by your existing controller. Is most of this in your backyard? If so, I don't see any reason not to operate the drip system from there instead of replacing everything and going from the front -- it shouldn't all need replaced unless you've got a ton of leaks. That should be fairly unlikely as buried PVC is pretty durable. The backflow one of the estimators mentioned could be the only difficult part -- backflow is very important (required in almost every location), but there's a big caveat here: backflow might already exist -- if your dad or a professional put in the existing system, there's a very good chance they included backflow prevention. We can come back to this part, as you'll definitely want some and may need to get it tested if it's already installed, but it's not needed until you're running the system. Do you have photos and diagrams of the existing infrastructure you could send me? I think with just a little more information I could help you narrow things down even more (unless the above information was enough to help get you started!). Basically the big question is going to be the best place to start the system from (valve, hose bib or riser). You can send photos and diagrams at our contact us link here: help.dripdepot.com/support/tickets/new -- the contact us turns it into an email -- put "Attention: Adam" somewhere in the title or body and it will come to me -- I suspect you can save an incredible amount of money DIY'ing this (except perhaps the backflow) :)

If the 1/4" lines were feeding drippers or emitters of some type, most likely you'd still want a pressure regulator -- the times you can get away with not using one are when using pressure compensating emitters and the water source's pressure was within the pressure compensating emitter's operating pressure range (10-45 PSI is a common range) or when using higher pressure emitters (sprinklers, some misting nozzles, etc) :)

Hello! I think (I hope anyway!) I touched on that in the video, but it's a very good question -- if you already have low enough pressure that you're within operating range for your emitters, you can go without a regulator. In fact, adding a regulator in those situations could cause issues (dropping pressure below the operating pressure). Having that low of pressure is a rare occurrence, but it definitely does happen and it something to keep in mind when planning the irrigation system :)

Sounds like you'd likely need one if the irrigation is before the pressure reducer -- that's not a bad thing though, starting off with a healthy pressure helps is a good starting point in pretty much any irrigation system :)

Gene, if it's too fast for you, RU-vid has built in an easy fix that I'm happy to share -- at the bottom right of the video you'll see a cog wheel and a red square with white letters that say "HD." If you click that cog wheel you'll see an option labeled "Playback Speed." Clicking there allows you to slow down the speed of the video to 0.75, 0.5 or 0.25 its original speed -- at 0.75 things still sound normal :)