If we take writing it down as a making a video, they’ve been scientists since experimenting with how to remove a toilet flange. Love the videos Stud Pack, keep it up!
Well, when my kids did science fairs, they had to run the test 3 times. That helps balance out not getting the timing right, or discovering that the results were wildly different, showing that the experiment wasn't accurately controlled. Still, the experiment was well designed for keeping control variables consistent and only changing one thing at a time. Plus, running the same experiment 3 times would make for a slow video.
Yeah, the straight up simplicity is worth it even if the results were slightly worse, though with less fittings and pipes, there is less risk of pressure loss to begin with.
Even before the test I already knew that the H system would win. And as I said it before when I commented on your videos, you guys are not afraid of a little constructive criticism and putting other people’s theories to the test (when it makes sense) thank you for all your hard work and the time you take to read the comments. Now stop screwing around and finish that bathroom so we can see some real work on the stud pack lone star house hehe! 👍
@@frankyboy4409 now that you mention it... you bring up a really good point. I’ve seen a lot of new houses where they put the valves far away from the shower heads because according to them you “don’t get wet while turning them on” but the extra length of pipe means that the shower heads will keep dripping water for a longer period of time after they’ve been shut off. So my advice to prevent this issue is to use as less pipe as possible between the valves and the heads or nozzles.
@TJP 81 it absolutely won. Keep in mind that the name of the game was even flow and either nozzles of the same level kept delivering the same amount of water. And the difference between the top and bottom nozzles was less of that between the loop system.
absolutely awesome video. this is what separates stud pack from much of the competition. humility, the assumption that you don’t know everything , the willingness try something new and a genuine curiosity about construction science. the old TQM philosophy of constant and continual improvement lives on in stud pack.
“K.I.S.S.” Less fittings, less pipe, less time - no brainer! Guys go crazy with loops and crossovers on remodels around here but need to brush up on their Bernoulli. This is a pressurized system. Pressure builds from the end. Restrictions increase pressure. Testing or thinking of the free flow output alone doesn’t translate to the flow or balance once restriction (the sprays) are added. Great no-nonsense and simple tests!
Retired plumber, started using Uponor and expander PEX since it first came out, and I'll tell you this, you are correct in that you can cut in a line to add fittings, and the water in the line won't be that much of a problem, unlike copper, BUT, BUT, BUT, if you try to expand a piece of wet Uponor pipe, and the expander ring is ALSO wet, both the ring and the pipe will slide off the expander tool at the same time. Believe me, it sucks, if you're under a house or retrofitted home, and cutting in a line, and it's wet. FYI.
I love that you guys go the extra mile and aren't too proud to try out alternative approaches. This was really informative, thanks for taking the time to try everything out and share it with us.
Such a fun video, great job guys! I like the fact too that ultimately the plumbing scenario doesn't matter much since those jets can be individually tuned to the user's preference
Thank you so much for your time and effort on this project. I'm sure it took a long time but a very cool test. I love these types of comparisons of methods. Great job!
Probably my favorite SP video. It shows your interest in your subscribers, your humility in your work, your expertise in wanting to mentor, and, well, it was just plain funny. Great dad and son collab!
PSI change for water is about 1 psi per 28 inches of rise. So the bottom ones will flow more than the top with equal pipe lengths and fittings. To equalize them the bottom pipes need to have longer pieces of PEX and OR more 90° fittings to induce drag and therefore pressure drop. This approach however is not linear and the flow rate affects the induced drag. The higher the flow rate of the shower heads the worse the imbalance will be. However these shower heads will likely either be on or off so the flow will be consistent. Feed into the top two first so they have access to the feed with the least restrictions then add a big loop of pex and or 90° fittings before connecting to the lower ones. You'd have to experiment with how much/many for find the right amount of drag for the given flow. In actual use, and with the flow controls on the shower heads, it's all needless overkill. However, if the shower heads are replaced with higher flow units, then it becomes more important. Fun video, thanks! Edited for typo.
2.31 foot of head = 1psi change. as long as they have enough volume to feed it, there should be virtually no difference in that closely spaced setup. now if there was multiple nozzles from floor to ceiling, then yes it would be a nasty issue.
The manufacturer of the shower heads already solved the problem with the flow valves on each shower head. Making doing anything further than the absolute simplest option is basically like reaching around your ass to scratch your elbow.
This video was awesome! You guys are the best for reading the comments and putting the theories to the test! This was super fun to watch and I'd love to see more like this. Keep up the great work!
Thanks for trying the different ways of doing it and showing the results. I have 9 rental houses and I do the repairs and remodeling myself on my days off from my regular job. Your videos have helped me save time on several projects. Love your videos
The manhattan loop looked nice but I’m all about simplicity and I believe I’d go with the H pattern myself. Less things to fail in that setup. Great video guys. Love watching you guys get into your work.
Another great video. The pressure test and differences minimal as long as you have enough supply volume. To balance it fully you would need to ad additional restriction on the lower section to account for gravity losses. This is beyond overkill for a shower. The best solution is one that goes in fastest with the minimum number of fittings to get the job done. Stick with the H moving forward. The loop idea will works in horizontal balancing but not in vertical. You can't beat gravity.
Probably your best video yet. Not really surprised about the higher jets producing less water as the hydrostatic pressure is higher, as it takes more energy to fight gravity the higher you get. Excellent video.
As a trained engineer, I love a video like this. There is theory, and then there is practice. Sometimes, the differences created by practice totally overwhelm the theoretical. In this case, the actual pipe lengths, fitting resistance, etc. are big contributors to actual performance, while theoretical differences are overwhelmed. I would predict that the shortest length of piping and the least number of fitings would produce the highest flow and pressure and the highest volume. If the outlets are vertically separated thbn they would have to be balanced by a restriction to the lower heads. Moving the supply connection from the center to above the heads should make a difference, but testing would tell.
The best way albeit more expensive and time consuming would be to add a globe valve which is an metering valve to each branch and manually adjust them all to balance out pressure and volume,much like an old radiator system
@@pawpaw7646 ROTFLMFAO...Lots won't like it when I say this. BUT...Reality is...well..Reality!!!! Theory is...Exactly that...Theory!!!! You are wise beyond your years!!!!!! Great Comment!!!
You are correct, Theory does not equal reality. Plumbing electronics whatever it may be.. Example, (electronics) The Vacuum tube was not being designed to be used as an amplifier. Theory stated that the tubes should have done something else completely. It was only be accident that Reality "overwhelmed" Theory thus the Vacuum Tube changed electronics forever. This new theory of amplification circuitry eventually led to the design of Transistors. Theory is a great starting point and foundation, but that won't change the reality of application.
@@jeffliverman3401 you still have lower pressure than a simple H. The more connectors and pipe cause resistance which reduces pressure. Unless your adding pressure. KISS method wins out.
Its been so long since college that i cant do the calcs or a schematic anymore but generally speaking, water pressure is like direct electrical current in a lot of respects. Pressure drops off over distance in relation to material reaction. For electricity thats resistance for water pressure iirc its friction. For water the material absorbs the energy in the water, this fractionally, even if minutely lowering pressure. What that means is that straight runs from source to outlet with zero joints produce the least loss in pressure. Curving the pipe where it could be straight causes a increase in pressure loss, as its essentially constant collion with the pipe wall is what changes the vector. The more extreme the curve, maxing out at 90 degrees, leads to the most loss. Additional changes like say more 90 degree turns further lowers the volume. I know plumbing is limited by existing fittings and code. Great video guys. If you know and civil or mechanical engineers they should be able to actually do math on sometging like this and produce a couple diagrams
Grady @Practicalengineering (on RUclips) does a lot on water systems. His focus is more on municipal sized systems (both water in and sewage out). He's pretty smart and I'm betting he has the formulas (or can write them) on the Engineering. Bonus fact is he's in Texas (San Antonio) so it wouldn't take extensive travel for a collaboration, but a zoom or email exchange would probably work. I mean if you want to know right down to the nitty gritty formulas and equations, I'm betting he's the guy. I hope he doesn't mind me saying all that.
I have 3 jets in a vertical line in my shower. The plumbers installed an equalization loop but it didn’t do anything. Bottom sprayer was putting out a lot of water , top was just barely spraying out. I spent an entire day taking apart sprayers and restricting the bottom with plastic washers and reassembling over and over until it was equal. In retrospect I wish they had installed a simple branch with ball valves to control the flow of each one . It would have been much simpler. The equalization loops don’t work.
@TJP 81 balancing valves and/or circuit setters. In essence, they are the same thing as a valve, but have an indicator which allows you to know how much it is open/closed and a screw to keep locked at desired opening.
The pipe size is probably much to small too feed them all at once. Should probably have it connected on the top first and then longer pipes for the lower ones. Or just change to more restrictive shower heads
Loops work in the horizontal and CAN help vertically as well. But generally loops allow for fixtures to be fed from both sides of the loop to mitigate the flow loss at the end of a branch. They won't correct for vertical head differential though. If you have a lot of plastic fittings on your feeder line, they will all add dynamic pressure and flow losses that can be significant. The brass AquaPEX fitting don't do this as their ID is the same as unexpanded pipe ID. It doesn't cost much more, due to the reduction in fittings and labor, to run each fixture back to a main manifold like a breaker box for electrical. The convenience of shutting any single fixture off from one location is a great feature, and makes future remodeling and fixture upgrades/relocations a dream.
Loved this video. Your willingness to say I'm wrong (if you would have been wrong) is so refreshing. You can definitely tell you love your work and I for one appreciate a contractor that takes the pride in their craft that you do. Please keep up the amazing videos so us Harry Homeowners don't have to do the trial-and-error at our expense most of us can't afford to things once much less two or three times just to find it doesn't work. Love it guys....
Be careful cutting those fittings off. The slightest nick in the fitting can cause a leak. I usually cut the expansion ring off then heat the pex to slide it off the fitting.
Another benefit of PEX.. couldn't have done this test with copper.. =D. Would've missed out on all this fun.. this is definitely father/son quality time. Not only a great contractor teaching his son life skills, you are teaching viewers what it means to be a father, and what it looks like being a father in real life.. you are helping the world be a better place..
Wow! This was one of the most interesting and fun video I’ve seen that y’all have done! I really appreciate y’all taking the time to do the testing! So fun!!! Keep them coming I really look forward to seeing your videos each week! I’m definitely a fan!!
Wonderful demonstration. Very good information for all plumbers, Masters through apprentices. Although your spray heads had adjustability, not all of them do, starting out with equal flow and pressure is always the best start. I am an inspector for a large city, also a professor of Plumbing at our local Community College. I will be using this video to help apprentices understand basics and why we do what we do. Please preach to your Utube community how important it is to get into the trades. Stay Dry
I must say, you came up with a creative and elegant way of making the comparisons. One thing you didn’t mention is that with the expansion fittings there is less flow restriction per fitting than with the crimp on style.
@@brianhughes1456 With the regular sharkbite, yes. I have not used the new Sharkbite Pro I think they're called, so I don't know if those work any different. Any type of fitting where the diameter is narrower than the pipe will cause some flow restriction. With sharkbites it has to clamp onto the inside and the outside of the pipe, and that slightly smaller tube on the inside means the fitting is slightly narrower than the pipe.
I just bought a house and it needed a lot of work. I was looking for videos to fix a problem and found it and I was A StudPack Junkie from the first video!!! Before finding this Channel I was lost, but I am proud to stay that I’ve learned a ton from you two!!!! Guys I absolutely love your videos!!! Your both great at teaching in a way that everyone can learn from. KEEP IT UP!!! Can’t wait for the StudPack House!!! 💪🏽💪🏽💪🏽🏡
Great video guys and as always fun to watch. Something to remember with the Uponor pex A expansion system is that the allowable distance between fittings/expansion rings is dependent on the size pex-A pipe you are using. As an example…. 1/2” Pex-A with the expansion ring has to have a minimum of 2” between fittings… if I remember correctly. And that distance goes up as you go up in Pex-A size. Another nod to the “H” pattern with less fittings.
I love that you guys did a test based on the comments! You're definitely my go to channel for self home improvements because of that alone! As for the H versus O testing when it comes to water pressure I think of it the same as electronics; the water is going to always take the path of least resistance. With that being said having the same distance of line on the H system, and having equal paths of travel for the water makes way more sense than having the pressure from the O system equaling out the amount of water.
I like the analogy between water and electricity; that's exactly right. I hate that common phrase "always take the path of least resistance" though! Electricity (and water) do NOT always take the path of least resistance. For both of them, if the change in potential is the same across multiple paths, then they both take ALL paths. The amount of current in each path is inversely proportional to that path's resistance. To give an example, if you have a circuit with 2k Ohms of resistance, if you wire up a new 1k Ohm resistor in parallel, the "always takes the path of least resistance" literal meaning would predict that 100% of the current would go through the 1k Ohm resistor. But that's not what you find; instead only 2/3rds of the current goes through the 1k Ohm resistor and the other 1/3rd goes through the 2k Ohm path.
This is the Stud Pack version of Mythbusters! LOL Great work guys. The "H" makes a lot of sense to me as it takes fewer joints and connections and ease of installation. You don't need to make it complicated like that loop...OMG that looked crazy to me
Stud Pack Mythbusters...A new channel should Stud Pack ever find the desire to expand their RUclips Channels and presence!!!! Great Comment and thank you for the humor!!!
@@evenberg8499 Yes... I like where this is going... He could be a Jamie, or an Adam... or BOTH! LOL I like Adam's sayings: "Am I missing an Eyebrow?" "I reject your reality and substitute my own" all really good stuff.
Very interesting and informative content! Also your presentation is great, no crazy music or loud excessive talking, just straight forward and to the point. You have gained a subscriber and watcher. Y'all are welcome in Texas anytime.
I love how you show proof that we don't know what we are talking about instead of just telling us we don't know what we are talking about! Love this vid!!!
Great video. The science behind equal length pipes has been proven in the automotive world with performance parts, Exhaust headers use equal lenght pipes until they combine into one so each cylinder can exhale the same amount. I hope when i'm ready to do some renovations on my house i can find a contractor like you in Rochester NY. I know there are good ones out here just gotta find them! I also like the H set up as less fittings less complications = less chance for something to go wrong, also from another stand point much cheaper to make vs the loop.
Performance exhausts are a bit different: the issue isn't different cylinders having different back pressures. You have a single pulse of pressure each exhaust stroke and that travels down the pipe at a certain speed. Where pipes merge, you don't want pulses to arrive at the same time because then you're trying to exhaust into a high pressure region which is harder. Equal lengths mean the delay from each cylinder to the merge point cancels out. Therefore you will always have the time between cylinders exhausting at the merge point between successive high pressure waves
It gets a bit more complicated with scavenging where you actually try and get the high pressure wave from one cylinder to merge with the low pressure wave which follows the high pressure wave of a previous cylinder. However, for that you've got to tune the lengths a bit mroe carefully and it only works for specific rpm ranges
Same goes for heating systems, if the feeds and returns are in sum at an equal length at every radiator or buffer system then you have an equal distribution of heat. It's how biomass buffer systems are connected usually since you save a shitton of valves and fittings if you know what you are doing.
@@jameshogge True but in this case pressure will always be greater on the lower portion compared to the upper one because of head pressure being greater in the lower portion.
Used PEX for replumbing the house we bought. Replaced from the meter and installed a distribution box as well. My father was helping to dig the trench and do things with me under the house running the lines and removing the old stuff. He was dumbfounded at how fast I was able to replumb the house once the main line was replaced. Still have to remodel the kitchen and bathroom but they function for now and eventually will be adding a bathroom upstairs along with a master bedroom but it's all currently one big open room. The old setup had a bunch of breaks in the PVC and CPVC lines and crud in the steel lines... Yeah it was that bad. Someone had replaced some of the steel lines from the meter with 3/4" PVC but left some of the 1/2" steel in place at some point and did some fixes here and there with a mixture of PVC and CPVC under the house. Where the 3/4" pvc came in it was reduced then fed into a 1/2" CPVC tee which fed cold to the rest of the house on one side and to the sink on the other... The water heater was plumbed backwards and was cranked to the absolute max as well.
I replumbed an RV with Pex-A, lots of test fitting, but when it came time to blind assemble all the joints, it was a breeze, just let the expander hold the end open for about 30 seconds to give you more time to get it into position, have to hold it for a little longer but it really make connecting to somewhere you cant see and can only reach with your shoulder up to the opening, reaching into a near inaccessible space.
The other big advantage of PEX over copper and UPVC that we learnt from the valentine freeze in TX in Feb ,20 when we had no power for 5 days and 9f, that it doesn’t burst, split or crack like the other two. Great product.
Our kitchen water pipes froze every winter the first four winters we lived in our house (Iowa). Finally got that sorted out, but thanks to PEX we never had to deal with burst pipes.
Dual in-let drop ears (drop ear tees) for loop jets equals less fittings overall! I think the key is a real loop with no 90 degree turns at all, avoiding turbulence and flow loss.
Nice, love how you guys tested it. Loops are done for less fittings because there's specific in-line drop ears with two inlets you can get for it, which I believe just gives you better flow rate.(not sure about even pressure) Also size of the pipe can come into play like using 3/4 pex in entire shower, instead of 1/2 because the fittings with 1/2 inch can really choke the flow rate. Having those adjustable controls on the heads would assist with pressure issues anyway. Great job as always, I'm sure your client is gonna love their new showers regardless.
I am about to remodel my shower and needed this info. Great job. The only thing I will be changing is I will not have a shower head installed instead it wall be a rock water fall. I will have 6 jets and on opposite side of each other. 3 on one side with the diverter valve and 3 on the opposite side. I will have fun figuring this one out. Thanks for the info.
I just love experiments, I'm taking notes for my project to get things just right too, and to think when I first stumbled on this channel I thought it was just going to be electrical, surprise surprise - keep us with you in your journey's and thank you.
The only problem with this test is that it is an open flow test. You have no back pressure due to the shower heads. Other than that, good work. Fluid dynamics is tricky even on the nanosecond level because you have infinite resistance when a space is occupied but since its constantly in flow you get back pressure which changes resistence at each fitting rapidly.
"The more bends in the plumbing, the easier it is to stop up the drain." -Scotty I knew team H would win from the beginning because it makes the most sense from a hydraulic stand point. Good job gang, I like this type of video as well as the classic style.
@@stevebabiak6997 True. When I built my home I had a well and used 1" to feed the house. My comment was based on you're potentially running both showers simultaneously and approaching maximum flow for 3/4" pipe.
Very nice video. Great construction of the test and I loved the actual performing of it! Gotta say I was surprised by the results. Was always taught to go with the loop. Now I know....
great video guys .. and fun too. ignore all the whining comments. bottom line either way will work fine .. I'll do whatever is most symmetrical and efficient with pipe and fittings in the given circumstance. smooth travels to TX!
Pressure loops make a big difference in horizontal applications. Water takes path of least resistance like electricity. In this vertical setup the top sprayers only receive pressure by what can’t be released by the bottom sprayers then fight gravity and minor losses in pipe and fittings to go out the top sprayers. Great work!
There are few videos on YT that I would rate as "fantastic" this is one of them, I have wondered about this loop vs H for a VERY long time. Nice work, guys!
It would be very difficult to equalise the pressure between top and bottom jets in this vertical case. If you imagine the jets as being holes in a solid tank of water, there will always be higher pressure lower down due to the weight of the water higher up. To get rid of that you would have to intentionally restrict the lower two jets so there was a pressure drop equal to the increase
I wonder if they upsized to 3/4 pex and fittings going from the valve to the threaded spray adapter for the upper jets. It still restricts at the valve.
I think that the determining issue is that each 90° fitting has a volume/loss factor of about .9. Further, head pressure (lift) has to be considered. Another consideration is the distance (causing volume to increase) would increase the cost of hot water and response time to adjusting the temperature. The old rules seem to apply here: Fewer fitting and less distance equals better pressure.
My bathroom has no water jets, but I enjoyed watching your scientific water Pex test. It's the pressure that matters first, then the flow. Great video Stud Pack.
There is probably a dozen different ways to configure the loop, all could have been a different outcome. I'm impressed with the fact you went to the difficulty of testing it, you guys rock...
Great video content! I was thinking that pressure regulation won't matter too much once the heads are put on because they have water restrictors in them to only allow a certain amount of gallons per minute. So long as you have enough combined pressure which is greater than the amount of heads restrictor valve kind of like the aerator then no matter what type of hookup we go with or the length of hose it's going to be very minimal difference. For instance if each head does one gallon per minute and you have four heads then you just need to be able to have a water supply of more than 4 gallons per minute of water volume and pressure. Same concept as if you run a sink right near the water supply coming into the house versus running a sink 75 ft away at the back of the house if you turn them on at the exact same time you're still only going to have one gallon per minute of water coming through them at roughly the same pressure. Some people out there verify my thoughts. Let me know?
I 100% agree. Pressure is created from a restriction. The incoming pressure is constant, so depending on your restrictions (shower heads), the pressure will be equal to the incoming pressure or less, always less if water is flowing. As long as there is enough flow to provide the outputs, the pressure will be equal. With no shower heads, the pressure was probably close to zero, so all you are seeing is what the max flow is.
@@ADBBuild Well, not exactly. If this is 1/0 system, then it might be fine as it will always feed as much as possible. If it has the water flow control and you can regulate how much you are getting from those, then different pressure loss on each nozzle will result in uneven flow and if you regulate them to be equal at this volume, it will be messed up with different volumes. That's because the main control valve is on the inlet, not on the nozzles and depending on the design you will get more or less even flow to nozzles. So generally if you have flow control, you may not have enough flow to provide the outputs as you stated and this is a valid case for some of those showers.
A true balance pressure loop supplies water to both halves of the to equal the pressure out you still only have a loop with a missing supply slide. The Idea is water enters at two points at the ends and the middle sees full pressure.
Great analysis! Its all in the pipe hydraulics. Every time you add a fitting, its like adding more pipe length. Pressure is lost for every foot of pipe length (headloss). So a good rule of thumb is short pipe runs and minimize fittings. Fewer fittings translates to shorter pipe. Key items into the headloss is (of course) pipe length, but reducing velocity. Velocity kills you, if you can get a slightly reduced velocity, headloss can plummet. Easy way to do that is larger pipe. That way just small bump diameter in pipe reduces velocity a great deal (the power of r squared). Your simple H was short pipe run and fewer fittings. I doubt your velocities were too high, and when you put the fittings on, that reduced velocity more which helped. Gravity is also in play - higher up is lesser pressure for sure. Short loops like the right side are nice, but for short runs, the difference are not great. Im working on an apartment site of about 10 acres with one meter. We run a big loop so it balances it all better. Loops are great when you get into fairly long runs (this one is about a 1500' loop). Great content as always, I always look forward to your graat work and I'm sure the Texas project twill be fantastic.
The real secret is you need to arrange the flow through each nozzle so that the pressure loss in the upstream piping is minimal compared to the flow through the holes in the spray nozzles. If you had done a time study you would have noticed that you have slightly less total water coming out of the 4 nozzles that you had on the 4 open spigots. This is the same principle in laying out a lawn sprinkler system. The water lines need to be sized so that the greatest pressure drop is across the spray nozzles. That way each nozzle sprays the same volume regardless as to where it is located in the piping system. Comments from an LSU Chemical Engineer.
This video shows a through A-B testing. Trying it "both ways" and evaluating the results. VERY scientific. VERY through. More testing videos should do it this way. VERY good video, and a shining example of how a test should be done.
The intuition for a loop is correct when it comes to pressure balancing, neglecting head differential. But when it comes to flow balancing, there is another factor to consider, and that is the momentum of the flowing water itself. The loop actually will create losses of momentum through turbulence where two opposing flows necessarily meet somewhere in the loop, resulting in (believe it or not) heat losses through friction of water on water. Where in the loop this might occur is essentially unpredictable because it will be governed by slight variations in manufacturing along every inch of pipe let alone slight variations in installation. This is why your testing is showing differences horizontally and overall less flow with the loop. Remember how much knocking and potentially damage water hammer can cause in poorly designed systems? That is the same energy essentially being lost in the loop that would otherwise be directed to each shower head. A note on PEX: from my experience (PEX B, but seriously considering the shift to A), stepping up a size is well worth it, as the ID is much smaller than copper and with the fittings, smaller yet. So generally where 1/2" copper would be appropriate for an entire project, maybe a small house, I will run 3/4 PEX for the primary trunks and 1/2" to smaller fixtures, bath and shower getting 3/4 right up to the mixer/diverter. This is a pain since a lot of the fittings are sold as if it is a drop in replacement when basic mechanics (and experience) demonstrate that it is not. I do wonder if I am mistaken assuming this is the case for PEX A? Easy enough to find out I guess, but what's the fun in that?
With just open lines for all four outlets, you will get a completely different result than if you had the restriction of the actual shower nozzles that would provide back pressure on the system. With open lines, the lower two nozzles will have more flow due to gravity, which provides back pressure on the lower two, but none on the upper open fittings.
it also occurred to me that once the water is shut off, all the water in the system will drain out of the bottom fittings. which means the bigger the loop, the more water will come out of the bottom fittings.
How about you try having the water start above all the jets and then T off into the top jets and then right angle into the bottom jets. Like an "n". I feel gravity is affecting this more than the plumbing technique.
Put copper unions on all your plumbing fixtures, boom problems solved for repair and replacement. I'm a commercial plumber so any residential plumbing installs make me cringe regardless, respect your multi capabilities though and knowledge
Хобби
You two are now officially scientists. The only difference between screwing around and science is writing down your results.
If we take writing it down as a making a video, they’ve been scientists since experimenting with how to remove a toilet flange. Love the videos Stud Pack, keep it up!
and even closer to nuke scientists -- writing it down and independent verification of the reading
Well, when my kids did science fairs, they had to run the test 3 times. That helps balance out not getting the timing right, or discovering that the results were wildly different, showing that the experiment wasn't accurately controlled. Still, the experiment was well designed for keeping control variables consistent and only changing one thing at a time. Plus, running the same experiment 3 times would make for a slow video.
Yes. It’s now a science channel. Best study our physics.
Or making guesses, never having a way to prove it and then write books about it.
Another plus for the "H" pattern is easier access if there is ever a problem. Less joints less likelihood of problems also.
Yeah, the straight up simplicity is worth it even if the results were slightly worse, though with less fittings and pipes, there is less risk of pressure loss to begin with.
Even before the test I already knew that the H system would win. And as I said it before when I commented on your videos, you guys are not afraid of a little constructive criticism and putting other people’s theories to the test (when it makes sense) thank you for all your hard work and the time you take to read the comments. Now stop screwing around and finish that bathroom so we can see some real work on the stud pack lone star house hehe! 👍
Same, for me the simple reason is: less piping. Which also means less water in the systems, and thus faster-reacting controls.
@@frankyboy4409 now that you mention it... you bring up a really good point. I’ve seen a lot of new houses where they put the valves far away from the shower heads because according to them you “don’t get wet while turning them on” but the extra length of pipe means that the shower heads will keep dripping water for a longer period of time after they’ve been shut off. So my advice to prevent this issue is to use as less pipe as possible between the valves and the heads or nozzles.
@TJP 81 it absolutely won. Keep in mind that the name of the game was even flow and either nozzles of the same level kept delivering the same amount of water. And the difference between the top and bottom nozzles was less of that between the loop system.
These guys are the best!!
I believe the new plumbing code calls for the shower controls to be accessible without getting wet.
absolutely awesome video. this is what separates stud pack from much of the competition. humility, the assumption that you don’t know everything , the willingness try something new and a genuine curiosity about construction science. the old TQM philosophy of constant and continual improvement lives on in stud pack.
Team H!
Fewer fittings + Less pipe = less pressure loss. Cheaper too!
Fun video, thanks for sharing.
It would have been even less fittings if he had used the dual in-let drop ears for loop
Less fittings equal less chance of leaks
Less line turbulence too.
@@travisk5589 Not really much of a worry when pex is involved. The pex a the fittings will become more snug over time
@@zombiexpanda get some real world experience
“K.I.S.S.” Less fittings, less pipe, less time - no brainer! Guys go crazy with loops and crossovers on remodels around here but need to brush up on their Bernoulli. This is a pressurized system. Pressure builds from the end. Restrictions increase pressure. Testing or thinking of the free flow output alone doesn’t translate to the flow or balance once restriction (the sprays) are added. Great no-nonsense and simple tests!
Retired plumber, started using Uponor and expander PEX since it first came out, and I'll tell you this, you are correct in that you can cut in a line to add fittings, and the water in the line won't be that much of a problem, unlike copper, BUT, BUT, BUT, if you try to expand a piece of wet Uponor pipe, and the expander ring is ALSO wet, both the ring and the pipe will slide off the expander tool at the same time. Believe me, it sucks, if you're under a house or retrofitted home, and cutting in a line, and it's wet. FYI.
When I have to do this,I take some sandcloth and rough up the pipe surface before putting the ring on. It works EVERY time with no ring slide-back.
Just use propress like a real man
No it won’t…the old style expansion rings yes..the new rings have stops on them
@@krispyasfk2567 progress…lol… glorified shark bite you mean?
@@MrDarren5012 That has to be the dumbest and most ignorant thing I've ever heard
I love that you guys go the extra mile and aren't too proud to try out alternative approaches. This was really informative, thanks for taking the time to try everything out and share it with us.
I love your channel always responding to constructive criticism and not afraid to show your mistakes in the videos. Truly an inspiration.
Such a fun video, great job guys!
I like the fact too that ultimately the plumbing scenario doesn't matter much since those jets can be individually tuned to the user's preference
Thank you so much for your time and effort on this project. I'm sure it took a long time but a very cool test. I love these types of comparisons of methods. Great job!
Probably my favorite SP video. It shows your interest in your subscribers, your humility in your work, your expertise in wanting to mentor, and, well, it was just plain funny. Great dad and son collab!
PSI change for water is about 1 psi per 28 inches of rise. So the bottom ones will flow more than the top with equal pipe lengths and fittings.
To equalize them the bottom pipes need to have longer pieces of PEX and OR more 90° fittings to induce drag and therefore pressure drop. This approach however is not linear and the flow rate affects the induced drag. The higher the flow rate of the shower heads the worse the imbalance will be. However these shower heads will likely either be on or off so the flow will be consistent. Feed into the top two first so they have access to the feed with the least restrictions then add a big loop of pex and or 90° fittings before connecting to the lower ones. You'd have to experiment with how much/many for find the right amount of drag for the given flow.
In actual use, and with the flow controls on the shower heads, it's all needless overkill. However, if the shower heads are replaced with higher flow units, then it becomes more important.
Fun video, thanks!
Edited for typo.
2.31 foot of head = 1psi change. as long as they have enough volume to feed it, there should be virtually no difference in that closely spaced setup.
now if there was multiple nozzles from floor to ceiling, then yes it would be a nasty issue.
The manufacturer of the shower heads already solved the problem with the flow valves on each shower head. Making doing anything further than the absolute simplest option is basically like reaching around your ass to scratch your elbow.
Nice that you took the time to find this out!
This video was awesome! You guys are the best for reading the comments and putting the theories to the test! This was super fun to watch and I'd love to see more like this. Keep up the great work!
Thanks for trying the different ways of doing it and showing the results. I have 9 rental houses and I do the repairs and remodeling myself on my days off from my regular job. Your videos have helped me save time on several projects. Love your videos
I have been checking everyday for a new video. Glad to see it up. Y’all stay safe! 🙏🏼
The manhattan loop looked nice but I’m all about simplicity and I believe I’d go with the H pattern myself. Less things to fail in that setup. Great video guys. Love watching you guys get into your work.
Loop will maintain pressure better …
@@splinterinthemind5158 Prove it.
you guys are amazing, what a detailed test you did, loved it and laughed along the way. Enjoy your work,keep it up.
Another great video Studpack!!! Great side-by-side comparison!
Great content and great tests. I have re-plumbed a few places with copper, cpvc and pex. Pex is the clear winner in my opinion.
Saturday morning fun with a new video.Thank You guys. Keep up the good work!
I do more learning from you two than i could from any education given. Great chemistry you have, keep making these great videos.
When cutting off the wrong fitting. Make sure not to scratch the fitting with yours knife. It will cause a leak
Another great video. The pressure test and differences minimal as long as you have enough supply volume. To balance it fully you would need to ad additional restriction on the lower section to account for gravity losses. This is beyond overkill for a shower. The best solution is one that goes in fastest with the minimum number of fittings to get the job done. Stick with the H moving forward. The loop idea will works in horizontal balancing but not in vertical. You can't beat gravity.
@TJP 81 I have 65 psi on a Co-Op rural water system. MAkes for some nice hard showers and I love it
R u a Plumber 🪠?!
LOVE it !! It is fantastic to learn and have one's inner hypotheses put to real-world testing. Wicked good stuff guys.
Thanks for putting in the time, effort and $$ to test this out!
Probably your best video yet. Not really surprised about the higher jets producing less water as the hydrostatic pressure is higher, as it takes more energy to fight gravity the higher you get. Excellent video.
As a trained engineer, I love a video like this. There is theory, and then there is practice. Sometimes, the differences created by practice totally overwhelm the theoretical. In this case, the actual pipe lengths, fitting resistance, etc. are big contributors to actual performance, while theoretical differences are overwhelmed. I would predict that the shortest length of piping and the least number of fitings would produce the highest flow and pressure and the highest volume. If the outlets are vertically separated thbn they would have to be balanced by a restriction to the lower heads.
Moving the supply connection from the center to above the heads should make a difference, but testing would tell.
The best way albeit more expensive and time consuming would be to add a globe valve which is an metering valve to each branch and manually adjust them all to balance out pressure and volume,much like an old radiator system
In theory, there is no difference between theory and practice. In practice, there is.
@@pawpaw7646 ROTFLMFAO...Lots won't like it when I say this. BUT...Reality is...well..Reality!!!! Theory is...Exactly that...Theory!!!! You are wise beyond your years!!!!!! Great Comment!!!
You are correct, Theory does not equal reality. Plumbing electronics whatever it may be..
Example, (electronics) The Vacuum tube was not being designed to be used as an amplifier. Theory stated that the tubes should have done something else completely. It was only be accident that Reality "overwhelmed" Theory thus the Vacuum Tube changed electronics forever. This new theory of amplification circuitry eventually led to the design of Transistors.
Theory is a great starting point and foundation, but that won't change the reality of application.
@@jeffliverman3401 you still have lower pressure than a simple H. The more connectors and pipe cause resistance which reduces pressure. Unless your adding pressure. KISS method wins out.
You guys are the best. Amazing teachers and amazing fun. Thank you so much for all your videos.
freaking great! what a nice opportunity to do some testing! Great job guys
Its been so long since college that i cant do the calcs or a schematic anymore but generally speaking, water pressure is like direct electrical current in a lot of respects.
Pressure drops off over distance in relation to material reaction. For electricity thats resistance for water pressure iirc its friction. For water the material absorbs the energy in the water, this fractionally, even if minutely lowering pressure.
What that means is that straight runs from source to outlet with zero joints produce the least loss in pressure. Curving the pipe where it could be straight causes a increase in pressure loss, as its essentially constant collion with the pipe wall is what changes the vector. The more extreme the curve, maxing out at 90 degrees, leads to the most loss.
Additional changes like say more 90 degree turns further lowers the volume.
I know plumbing is limited by existing fittings and code.
Great video guys. If you know and civil or mechanical engineers they should be able to actually do math on sometging like this and produce a couple diagrams
Grady @Practicalengineering (on RUclips) does a lot on water systems. His focus is more on municipal sized systems (both water in and sewage out). He's pretty smart and I'm betting he has the formulas (or can write them) on the Engineering. Bonus fact is he's in Texas (San Antonio) so it wouldn't take extensive travel for a collaboration, but a zoom or email exchange would probably work. I mean if you want to know right down to the nitty gritty formulas and equations, I'm betting he's the guy. I hope he doesn't mind me saying all that.
I have 3 jets in a vertical line in my shower. The plumbers installed an equalization loop but it didn’t do anything. Bottom sprayer was putting out a lot of water , top was just barely spraying out. I spent an entire day taking apart sprayers and restricting the bottom with plastic washers and reassembling over and over until it was equal. In retrospect I wish they had installed a simple branch with ball valves to control the flow of each one . It would have been much simpler. The equalization loops don’t work.
@TJP 81 balancing valves and/or circuit setters. In essence, they are the same thing as a valve, but have an indicator which allows you to know how much it is open/closed and a screw to keep locked at desired opening.
The pipe size is probably much to small too feed them all at once.
Should probably have it connected on the top first and then longer pipes for the lower ones.
Or just change to more restrictive shower heads
@TJP 81 how would this differ from ball valves which I had suggested
Loops work in the horizontal and CAN help vertically as well. But generally loops allow for fixtures to be fed from both sides of the loop to mitigate the flow loss at the end of a branch. They won't correct for vertical head differential though. If you have a lot of plastic fittings on your feeder line, they will all add dynamic pressure and flow losses that can be significant. The brass AquaPEX fitting don't do this as their ID is the same as unexpanded pipe ID. It doesn't cost much more, due to the reduction in fittings and labor, to run each fixture back to a main manifold like a breaker box for electrical. The convenience of shutting any single fixture off from one location is a great feature, and makes future remodeling and fixture upgrades/relocations a dream.
@@mikemorgan5015 how would you correct for vertical generally , valves (restrictors)?
Loved the demonstration that y’all made! Thanks for sharing the great content !
Loved this video. Your willingness to say I'm wrong (if you would have been wrong) is so refreshing. You can definitely tell you love your work and I for one appreciate a contractor that takes the pride in their craft that you do. Please keep up the amazing videos so us Harry Homeowners don't have to do the trial-and-error at our expense most of us can't afford to things once much less two or three times just to find it doesn't work. Love it guys....
Be careful cutting those fittings off. The slightest nick in the fitting can cause a leak.
I usually cut the expansion ring off then heat the pex to slide it off the fitting.
Yup. With Uponor that is how they instruct to remove the old fitting; cut the ring and heat the PEX. But plastic isn't to be reused
Wow we got a couple of know-it-all-yet-know-nothings here lol
"slightest nick in the fitting can cause a leak"
That's what your mom said the night you were conceived...
This is an important fact.
been there done that, third time repairing was the charm 🙄😬
Loving the project Stud pack water test. We need more of this type of content when possible. Keep up good work guys From NYC.
Appreciate that you take the time to analyze the suggestions… net result is the logical and cost effective installation prevailed
Not many people would take the time to do this even less videoing and sharing it! I love it, thanks for taking the time!
Another benefit of PEX.. couldn't have done this test with copper.. =D. Would've missed out on all this fun.. this is definitely father/son quality time. Not only a great contractor teaching his son life skills, you are teaching viewers what it means to be a father, and what it looks like being a father in real life.. you are helping the world be a better place..
Yes you could have? He used drop ear 90s with male adapters threaded into them.
Couldn't wait on the next video to watch, you guys are awesome
Wow! This was one of the most interesting and fun video I’ve seen that y’all have done! I really appreciate y’all taking the time to do the testing! So fun!!! Keep them coming I really look forward to seeing your videos each week! I’m definitely a fan!!
Wonderful demonstration. Very good information for all plumbers, Masters through apprentices.
Although your spray heads had adjustability, not all of them do, starting out with equal flow and pressure is always the best start.
I am an inspector for a large city, also a professor of Plumbing at our local Community College. I will be using this video to help apprentices understand basics and why we do what we do.
Please preach to your Utube community how important it is to get into the trades.
Stay Dry
That’s awesome thx Bill!! And thx for teaching the trades… so important and much needed now more than ever 👊👍
I must say, you came up with a creative and elegant way of making the comparisons. One thing you didn’t mention is that with the expansion fittings there is less flow restriction per fitting than with the crimp on style.
how about with the shark bite fitting, would those too have more restriction?
@@brianhughes1456 With the regular sharkbite, yes. I have not used the new Sharkbite Pro I think they're called, so I don't know if those work any different.
Any type of fitting where the diameter is narrower than the pipe will cause some flow restriction. With sharkbites it has to clamp onto the inside and the outside of the pipe, and that slightly smaller tube on the inside means the fitting is slightly narrower than the pipe.
I just bought a house and it needed a lot of work. I was looking for videos to fix a problem and found it and I was A StudPack Junkie from the first video!!! Before finding this Channel I was lost, but I am proud to stay that I’ve learned a ton from you two!!!! Guys I absolutely love your videos!!! Your both great at teaching in a way that everyone can learn from. KEEP IT UP!!! Can’t wait for the StudPack House!!! 💪🏽💪🏽💪🏽🏡
Great video guys and as always fun to watch. Something to remember with the Uponor pex A expansion system is that the allowable distance between fittings/expansion rings is dependent on the size pex-A pipe you are using. As an example…. 1/2” Pex-A with the expansion ring has to have a minimum of 2” between fittings… if I remember correctly. And that distance goes up as you go up in Pex-A size. Another nod to the “H” pattern with less fittings.
I love that you guys did a test based on the comments! You're definitely my go to channel for self home improvements because of that alone! As for the H versus O testing when it comes to water pressure I think of it the same as electronics; the water is going to always take the path of least resistance. With that being said having the same distance of line on the H system, and having equal paths of travel for the water makes way more sense than having the pressure from the O system equaling out the amount of water.
The 90 degree bends also drop some pressure.
I like the analogy between water and electricity; that's exactly right. I hate that common phrase "always take the path of least resistance" though! Electricity (and water) do NOT always take the path of least resistance. For both of them, if the change in potential is the same across multiple paths, then they both take ALL paths. The amount of current in each path is inversely proportional to that path's resistance.
To give an example, if you have a circuit with 2k Ohms of resistance, if you wire up a new 1k Ohm resistor in parallel, the "always takes the path of least resistance" literal meaning would predict that 100% of the current would go through the 1k Ohm resistor. But that's not what you find; instead only 2/3rds of the current goes through the 1k Ohm resistor and the other 1/3rd goes through the 2k Ohm path.
This is the Stud Pack version of Mythbusters! LOL Great work guys. The "H" makes a lot of sense to me as it takes fewer joints and connections and ease of installation. You don't need to make it complicated like that loop...OMG that looked crazy to me
Stud Pack Mythbusters...A new channel should Stud Pack ever find the desire to expand their RUclips Channels and presence!!!! Great Comment and thank you for the humor!!!
Paul should start growing a mustache and wear a beret. 😊
@@evenberg8499 Yes... I like where this is going... He could be a Jamie, or an Adam... or BOTH! LOL I like Adam's sayings: "Am I missing an Eyebrow?" "I reject your reality and substitute my own" all really good stuff.
Very interesting and informative content! Also your presentation is great, no crazy music or loud excessive talking, just straight forward and to the point. You have gained a subscriber and watcher. Y'all are welcome in Texas anytime.
I love how you show proof that we don't know what we are talking about instead of just telling us we don't know what we are talking about! Love this vid!!!
Great video. The science behind equal length pipes has been proven in the automotive world with performance parts, Exhaust headers use equal lenght pipes until they combine into one so each cylinder can exhale the same amount. I hope when i'm ready to do some renovations on my house i can find a contractor like you in Rochester NY. I know there are good ones out here just gotta find them! I also like the H set up as less fittings less complications = less chance for something to go wrong, also from another stand point much cheaper to make vs the loop.
Less potential points for leaks also. Less joints would easily be a winner for me.
Performance exhausts are a bit different: the issue isn't different cylinders having different back pressures.
You have a single pulse of pressure each exhaust stroke and that travels down the pipe at a certain speed. Where pipes merge, you don't want pulses to arrive at the same time because then you're trying to exhaust into a high pressure region which is harder.
Equal lengths mean the delay from each cylinder to the merge point cancels out. Therefore you will always have the time between cylinders exhausting at the merge point between successive high pressure waves
It gets a bit more complicated with scavenging where you actually try and get the high pressure wave from one cylinder to merge with the low pressure wave which follows the high pressure wave of a previous cylinder. However, for that you've got to tune the lengths a bit mroe carefully and it only works for specific rpm ranges
Same goes for heating systems, if the feeds and returns are in sum at an equal length at every radiator or buffer system then you have an equal distribution of heat. It's how biomass buffer systems are connected usually since you save a shitton of valves and fittings if you know what you are doing.
@@jameshogge True but in this case pressure will always be greater on the lower portion compared to the upper one because of head pressure being greater in the lower portion.
Used PEX for replumbing the house we bought. Replaced from the meter and installed a distribution box as well. My father was helping to dig the trench and do things with me under the house running the lines and removing the old stuff. He was dumbfounded at how fast I was able to replumb the house once the main line was replaced. Still have to remodel the kitchen and bathroom but they function for now and eventually will be adding a bathroom upstairs along with a master bedroom but it's all currently one big open room.
The old setup had a bunch of breaks in the PVC and CPVC lines and crud in the steel lines... Yeah it was that bad. Someone had replaced some of the steel lines from the meter with 3/4" PVC but left some of the 1/2" steel in place at some point and did some fixes here and there with a mixture of PVC and CPVC under the house. Where the 3/4" pvc came in it was reduced then fed into a 1/2" CPVC tee which fed cold to the rest of the house on one side and to the sink on the other... The water heater was plumbed backwards and was cranked to the absolute max as well.
I replumbed an RV with Pex-A, lots of test fitting, but when it came time to blind assemble all the joints, it was a breeze, just let the expander hold the end open for about 30 seconds to give you more time to get it into position, have to hold it for a little longer but it really make connecting to somewhere you cant see and can only reach with your shoulder up to the opening, reaching into a near inaccessible space.
I love your highly scientific testing methods. You're a hoot to watch and not only that, but very educational. Thank you.
Interesting test. Thank you for sharing the results.
That was fun. That first loop was crazy. I thought it was silly looking. The second loop sure used a lot of fittings. I'd go with the H.
The other big advantage of PEX over copper and UPVC that we learnt from the valentine freeze in TX in Feb ,20 when we had no power for 5 days and 9f, that it doesn’t burst, split or crack like the other two. Great product.
Our kitchen water pipes froze every winter the first four winters we lived in our house (Iowa). Finally got that sorted out, but thanks to PEX we never had to deal with burst pipes.
i love watching you two!! thanks for all that you do.
Nice video! Great experiment and glad you guys went so thorough with it to leave little doubt.
Dual in-let drop ears (drop ear tees) for loop jets equals less fittings overall! I think the key is a real loop with no 90 degree turns at all, avoiding turbulence and flow loss.
Nice, love how you guys tested it. Loops are done for less fittings because there's specific in-line drop ears with two inlets you can get for it, which I believe just gives you better flow rate.(not sure about even pressure) Also size of the pipe can come into play like using 3/4 pex in entire shower, instead of 1/2 because the fittings with 1/2 inch can really choke the flow rate. Having those adjustable controls on the heads would assist with pressure issues anyway. Great job as always, I'm sure your client is gonna love their new showers regardless.
Pex A fittings are full flow and do not restrict the flow like Pex B or C. Turbulence is a different issue with 90's...
I think the client is their business. They are the clients.
I am about to remodel my shower and needed this info. Great job. The only thing I will be changing is I will not have a shower head installed instead it wall be a rock water fall. I will have 6 jets and on opposite side of each other. 3 on one side with the diverter valve and 3 on the opposite side. I will have fun figuring this one out. Thanks for the info.
I just love experiments, I'm taking notes for my project to get things just right too, and to think when I first stumbled on this channel I thought it was just going to be electrical, surprise surprise - keep us with you in your journey's and thank you.
I’m impressed by all the testing , as a plumber I can appreciate the results . Because these are things we want to know
The only problem with this test is that it is an open flow test. You have no back pressure due to the shower heads. Other than that, good work. Fluid dynamics is tricky even on the nanosecond level because you have infinite resistance when a space is occupied but since its constantly in flow you get back pressure which changes resistence at each fitting rapidly.
Thanks for this video!!, saves me a lot of time on plumbing pex tubing and fittings, and the 'H' configuration!!
Just stumbled on your channel today. So much great content! You are very informative and concise. And this video was amazing! Subscribed!
"The more bends in the plumbing, the easier it is to stop up the drain."
-Scotty
I knew team H would win from the beginning because it makes the most sense from a hydraulic stand point. Good job gang, I like this type of video as well as the classic style.
yo. this has nothing to do with the drain. bends will not stop up the water inlet supply.
Extremely important video! If I were doing this double-shower multiple-outlets system in my own home I think I would feed it with 1" pipe, not 3/4."
Not sure that would buy you much if anything, since all of the residential water supply I have seen is 3/4”.
@@stevebabiak6997 True. When I built my home I had a well and used 1" to feed the house. My comment was based on you're potentially running both showers simultaneously and approaching maximum flow for 3/4" pipe.
@@stevebabiak6997
which reminds me; water-hammer wasn't a problem to address in your Auto Garage Buddy's showers?
@@choimdachoim9491 - I am not the one who made this video, don’t know if there are any water hammer issues.
Really nice to see you guys running these tests.
Very nice video. Great construction of the test and I loved the actual performing of it! Gotta say I was surprised by the results. Was always taught to go with the loop. Now I know....
great video guys .. and fun too. ignore all the whining comments. bottom line either way will work fine .. I'll do whatever is most symmetrical and efficient with pipe and fittings in the given circumstance. smooth travels to TX!
Pressure loops make a big difference in horizontal applications. Water takes path of least resistance like electricity. In this vertical setup the top sprayers only receive pressure by what can’t be released by the bottom sprayers then fight gravity and minor losses in pipe and fittings to go out the top sprayers. Great work!
Love it. I'm glad you guys did that test.
There are few videos on YT that I would rate as "fantastic" this is one of them, I have wondered about this loop vs H for a VERY long time. Nice work, guys!
It would be very difficult to equalise the pressure between top and bottom jets in this vertical case. If you imagine the jets as being holes in a solid tank of water, there will always be higher pressure lower down due to the weight of the water higher up.
To get rid of that you would have to intentionally restrict the lower two jets so there was a pressure drop equal to the increase
You could add longer piping to the lower jets to reduce flow and equalize the output of the lower vs the upper jets.
I wonder if they upsized to 3/4 pex and fittings going from the valve to the threaded spray adapter for the upper jets. It still restricts at the valve.
I think that the determining issue is that each 90° fitting has a volume/loss factor of about .9. Further, head pressure (lift) has to be considered. Another consideration is the distance (causing volume to increase) would increase the cost of hot water and response time to adjusting the temperature. The old rules seem to apply here: Fewer fitting and less distance equals better pressure.
If it was crimp pex the flow restriction will be greater. Expansion no different than copper. Love pex a
Ya dont get those flow issues with Copper.
My bathroom has no water jets, but I enjoyed watching your scientific water Pex test. It's the pressure that matters first, then the flow. Great video Stud Pack.
There is probably a dozen different ways to configure the loop, all could have been a different outcome.
I'm impressed with the fact you went to the difficulty of testing it, you guys rock...
Great video content!
I was thinking that pressure regulation won't matter too much once the heads are put on because they have water restrictors in them to only allow a certain amount of gallons per minute. So long as you have enough combined pressure which is greater than the amount of heads restrictor valve kind of like the aerator then no matter what type of hookup we go with or the length of hose it's going to be very minimal difference.
For instance if each head does one gallon per minute and you have four heads then you just need to be able to have a water supply of more than 4 gallons per minute of water volume and pressure.
Same concept as if you run a sink right near the water supply coming into the house versus running a sink 75 ft away at the back of the house if you turn them on at the exact same time you're still only going to have one gallon per minute of water coming through them at roughly the same pressure.
Some people out there verify my thoughts. Let me know?
I 100% agree. Pressure is created from a restriction. The incoming pressure is constant, so depending on your restrictions (shower heads), the pressure will be equal to the incoming pressure or less, always less if water is flowing. As long as there is enough flow to provide the outputs, the pressure will be equal. With no shower heads, the pressure was probably close to zero, so all you are seeing is what the max flow is.
@@ADBBuild Well, not exactly. If this is 1/0 system, then it might be fine as it will always feed as much as possible. If it has the water flow control and you can regulate how much you are getting from those, then different pressure loss on each nozzle will result in uneven flow and if you regulate them to be equal at this volume, it will be messed up with different volumes. That's because the main control valve is on the inlet, not on the nozzles and depending on the design you will get more or less even flow to nozzles. So generally if you have flow control, you may not have enough flow to provide the outputs as you stated and this is a valid case for some of those showers.
A true balance pressure loop supplies water to both halves of the to equal the pressure out you still only have a loop with a missing supply slide. The Idea is water enters at two points at the ends and the middle sees full pressure.
bs lol
Great video, I went down this rabbit hole when I did a bathroom remodel. Now everyone can see the difference.
Y'all are having too much fun!
Good stuff!
Great analysis! Its all in the pipe hydraulics. Every time you add a fitting, its like adding more pipe length. Pressure is lost for every foot of pipe length (headloss). So a good rule of thumb is short pipe runs and minimize fittings. Fewer fittings translates to shorter pipe. Key items into the headloss is (of course) pipe length, but reducing velocity. Velocity kills you, if you can get a slightly reduced velocity, headloss can plummet. Easy way to do that is larger pipe. That way just small bump diameter in pipe reduces velocity a great deal (the power of r squared). Your simple H was short pipe run and fewer fittings. I doubt your velocities were too high, and when you put the fittings on, that reduced velocity more which helped. Gravity is also in play - higher up is lesser pressure for sure. Short loops like the right side are nice, but for short runs, the difference are not great. Im working on an apartment site of about 10 acres with one meter. We run a big loop so it balances it all better. Loops are great when you get into fairly long runs (this one is about a 1500' loop). Great content as always, I always look forward to your graat work and I'm sure the Texas project twill be fantastic.
The real secret is you need to arrange the flow through each nozzle so that the pressure loss in the upstream piping is minimal compared to the flow through the holes in the spray nozzles. If you had done a time study you would have noticed that you have slightly less total water coming out of the 4 nozzles that you had on the 4 open spigots. This is the same principle in laying out a lawn sprinkler system. The water lines need to be sized so that the greatest pressure drop is across the spray nozzles. That way each nozzle sprays the same volume regardless as to where it is located in the piping system. Comments from an LSU Chemical Engineer.
This video shows a through A-B testing. Trying it "both ways" and evaluating the results. VERY scientific. VERY through. More testing videos should do it this way. VERY good video, and a shining example of how a test should be done.
this was a long time committment on the experiment but absolutely I loved it!!!👍
The intuition for a loop is correct when it comes to pressure balancing, neglecting head differential. But when it comes to flow balancing, there is another factor to consider, and that is the momentum of the flowing water itself. The loop actually will create losses of momentum through turbulence where two opposing flows necessarily meet somewhere in the loop, resulting in (believe it or not) heat losses through friction of water on water. Where in the loop this might occur is essentially unpredictable because it will be governed by slight variations in manufacturing along every inch of pipe let alone slight variations in installation. This is why your testing is showing differences horizontally and overall less flow with the loop.
Remember how much knocking and potentially damage water hammer can cause in poorly designed systems? That is the same energy essentially being lost in the loop that would otherwise be directed to each shower head.
A note on PEX: from my experience (PEX B, but seriously considering the shift to A), stepping up a size is well worth it, as the ID is much smaller than copper and with the fittings, smaller yet. So generally where 1/2" copper would be appropriate for an entire project, maybe a small house, I will run 3/4 PEX for the primary trunks and 1/2" to smaller fixtures, bath and shower getting 3/4 right up to the mixer/diverter. This is a pain since a lot of the fittings are sold as if it is a drop in replacement when basic mechanics (and experience) demonstrate that it is not.
I do wonder if I am mistaken assuming this is the case for PEX A?
Easy enough to find out I guess, but what's the fun in that?
With just open lines for all four outlets, you will get a completely different result than if you had the restriction of the actual shower nozzles that would provide back pressure on the system. With open lines, the lower two nozzles will have more flow due to gravity, which provides back pressure on the lower two, but none on the upper open fittings.
it also occurred to me that once the water is shut off, all the water in the system will drain out of the bottom fittings. which means the bigger the loop, the more water will come out of the bottom fittings.
I've been watching/enjoying your videos for quite some time. This test right here made me subscribe to your channel. Keep up the good work.
You guys are awesome. Thank you for sharing all your knowledge.
I was on team H. Good job, but nextime you test the water jets wear a big trash bag! 🤣
How about you try having the water start above all the jets and then T off into the top jets and then right angle into the bottom jets. Like an "n". I feel gravity is affecting this more than the plumbing technique.
The "n" configuration is what I was thinking, the extra pipe would compensate for the gravity assist.
great job paul and jordan, this was an eye opener....
Thank you for working WAY harder to help us understand!
When doing experiments like that, you guys should wear white lab coats 😂😂
Put copper unions on all your plumbing fixtures, boom problems solved for repair and replacement. I'm a commercial plumber so any residential plumbing installs make me cringe regardless, respect your multi capabilities though and knowledge
You guys are AMAZING and so efficient!
You guys are awesome! Thanks for the extra scientific test!
DIRTY, GREASY, TIRED, I don't care what the design is, the fact that I am getting multiple jets in one shower is r a GREAT way to end the day.
I love the bucket catch system.. you guys are great.