Water pressure versus water flow

It’s easy to get confused between water pressure and water flow. Many times you will hear people say that they are going to close their stop tap to reduce the pressure. Whilst it is possible to reduce the pressure slightly with a stop tap you are actually reducing the flow and not the pressure. This video explains the difference between flow and pressure using an inexpensive water pressure test gauge fave.co/1IPpqKm
These videos might also help-
How to measure water pressure- • How to measure water p...
How to measure water flow- • How to measure water f...
If you need to install a pressure reducing valve this article shows how to do it- www.ultimatehandyman.co.uk/how...

[@chrismortimer3808]

Quality. Nice work mate -I found that really useful. Thanks for taking the time to film and post it.

[@ultimatehandyman]

You are welcome. Thanks for the comment ;-

[@jacobleedowney]

One of those principals that is so simple yet seems so complicated. Thanks for helping me make sure I'm thinking correct. XD

[@ultimatehandyman]

You are welcome Thanks for the comment

[@jackjill3205]

+Ultimate Handyman Hi, I am looking to have a saniflo sanicmpact installed. Technical advice the following: Sanicompact requires 1.7 bar *_dynamic incoming water pressure_* (i.e. measured whilst the water is flowing into the Sanicompact and not static pressure I am told that *dynamic incoming water pressure* is not the same as static pressure Can you advice how I can test for this *dynamic incoming water pressure* Thanks in advance

[@tommymartin5555]

you live up to your name man. I really like your videos

[@ultimatehandyman]

+Tommy Martin Thanks Tommy ;-)

[@acidrain55]

Beautiful video thanks!

[@ultimatehandyman]

You are welcome Thanks for the comment

[@zedman442]

Great explanation as always. Contrary to popular belief you can pump mains water, however only to the recommended 12l/min. Something like a salamander homeboost which will raise the flow rate of it dips below this. Useful for combi boilers where flow rate is important. You have plenty of fly by night plumbers that never check the flow rate before installing a combi!

[@ultimatehandyman]

+Zed Man Thanks, I didn't know you could pump mains water. I'm sure people in the past have said it is not possible to pump mains water. I'll take a look at one of those pumps!Thanks for the comment ;-)

[@joannacolhoun133]

I’m using a pressure reducer that came with my hose lock irrigation system but it makes a horrible loud noise through the house whilst the system is on so I was hoping I wouldn’t need the pressure reducer?

[@steves1460]

You have an omni-presence! Everything I search for, there you are. I’m sure if I was to search, for example, male impotency, you’d have a video on that as well! :-)

[@ultimatehandyman]

I've not got there yet, but if I was struggling in that area, I would just trade the girlfriend in for a younger model- I'm sure that would work ;-) Thanks for the comment 👍

[@crazylove2426]

He is the ULTIMATE handyman

[@fishrod6298]

Great video man! Can I ask your opinion? If I'm using water to generate electricity in a hydroelectric system , (water flow from a river spins the pelton wheel that is connected to a modified stator), however I want to reproduce that system on a home domestic house , without a river, would upping the psi / or pressure net the same result as the flow from a river ? I can't work it out, and it's a heck of a bad way to find out if I'm wrong, for my back pocket haha

[@ultimatehandyman]

I'm not sure, but you would need a real lot of flow to get anywhere what a river can produce!

[@macmusica]

@@ultimatehandyman are you saying we can not put a hydroelectric generator in our unused baths for free electric? really? water gets cycled back again so there is no loss hehe!

[@ChrisTheSparky]

I use this when explaining Voltage and Amps. Voltage is the pressure pushing the electricity along and Amps is the amount of electricity that's there.

[@ultimatehandyman]

+bilzup Thanks for the comment ;-)

[@ultimatehandyman]

+bilzup Thanks for the comment ;-)

[@TiberiusStorm]

bilzup: So the current or amps is the water in that explanation?

[@amirhussain1449]

nice one,I'll have to try what you did in this video

[@ultimatehandyman]

+amir hussain You are welcome ;-) Thanks for the comment

[@jeffbowen6456]

Pressure v Flow, we just want the “Force” to be with us. Strangely during the first weeks of lockdown, we notice the force of water from our taps drop. We live in a very old hose, built around 1920 and previously if we were to turn the cold tap in the kitchen on and off quickly we would hear a bang in the pipes, this bang had now stopped. Good thing you would think, but this drop in “force” has had a secondary impact in that when we run the hot tap for the bath or shower, the combi boiler doesn’t fire up. If we turn the hot taps on in the bath, bathroom sink and kitchen at the same time, the boiler works fine. We called the water company, who came out to test things. The engineer could not come into the house due to their Covid 19 precautions but was able to test things from our garden tap. He said the pressure was fine at 5 bar but the flow was very low at 0.4 litres per static head minutes. He said it was most likely the main stop tap outside the house so would arrange for it to be replaced. This has now been done and there is a new black plastic one instead of the old brass one that was there. However, it has made no difference to the problems we have, any ideas on what we can do next?

[@flanderstf]

Thanks. SO will a pressure reducing valve lessen the water flow ?

[@ultimatehandyman]

No, a Pressure reducing vale will only reduce the pressure, although it might slightly reduce the flow it should not be noticeable. Thanks for the comment

[@gavinhooper1362]

If I upgrade my current supply pipe which is 20m long from the Southern Water meter in the footpath from a 22mm outside diameter to say a larger 35mm (at silly cost incurred by water authority as its considered a new connection) would i benefit greatly, will i loose pressure ? The reason for considering is because im looking to have a loft conversion done with an ensuite bathroom. thanks

[@ultimatehandyman]

I don't know, sorry. Who recommended the larger diameter pipe?

[@Diehard65]

You would not lose pressure but what you would gain depends on the flow rate. Roughly speaking, in a 20m length of pipe, and at a 10 GPM flow, you should gain about 10 to 15 psi pressure due to the reduction in pressure loss through the larger pipe. At lower flows it would be lesser gains, since you have less pressure loss at lower flows to begin with. In other words the higher the required flows the higher the pressure loses and the more there is to gain with a larger pipe. I hope I didn't lose you.

[@curiosity2314]

100 PSI is pretty high, I think standard here in the U.S. is around 60. Costs around 50 dollars a month here in Illinois for 4000 gallons usage. How does it compare? Part of that bill is for sewage maintenance.

[@ultimatehandyman]

+Curiosity Where I live it depends on the rateable value of your home( I think ), unless you have a water meter installed. Newer properties tend to have water meters installed, or you can request to have one installed if you like. I just checked the last bill and it works out at $780 for the year, which includes them charging you for the waste water run off from gutters etc. There is no limitation to how much water we can use, although we very rarely use it for gardening etc. as we get a huge amount of rain over a 12 month period.On the face of it I would say that we are being ripped off over here as we get lots of rainfall, which I'm guessing you don't get in the U.S? I remember seeing reports on RT that parts of the U.S have never had so little water, I think it was in the Vegas area? Thanks for the comment, it is good to know what people in other countries pay ;-)

[@benjames6431]

So pressure is the force pushing the water along and flow is the amount of water you have to push at any one time?

[@ultimatehandyman]

+Ben James Yes, that's sound like a good explanation of it to me ;-) Thanks for the comment

[@JohnUk65]

do you know of anything to increase water pressure for my outside tap as mine is very low..? thanks

[@ultimatehandyman]

+Mr Slim Guy 65 There is not much you can do about it to be honest, unless you have high pressure elsewhere which could mean that there is a faulty valve/check valve restricting the flow to it?

[@JohnUk65]

ok will do i'll try that!! many thanks..

[@Sheena1234ization]

I have 7 bar pressure, there's lots of noise when taps run. Should I reduce the volume or pressure?

[@ultimatehandyman]

Reducing the pressure is difficult and would require installing a pressure reducing valve, you can reduce the flow somewhat by closing the incoming stop tap slightly.

[@Sheena1234ization]

Thanks. Which would reduce noise from taps the most in your opinion?

[@kaiser9100]

Nice one. I hope that house has a PRV fitted!

[@ultimatehandyman]

+kaiser9100 Not that I'm aware of. The incoming water main is boxed in with just a small access hole for the stopcock. I have bought a shock arrestor but have not had chance to fit it yet. Getting access to the incoming water main to fit a PRV is not going to be an easy job! The stopcock is quite literally only open by a quarter of one turn, if you open it any more than a quarter turn you get really bad water hammer! Thanks for the comment ;-)

[@cliffcarlo180]

Electric cable so close to a water supply always makes me a touch nervous lol Merry Christmas and all the best for 2016.

[@ultimatehandyman]

+Cliff Carlo LOL, it's Pyro cable I think. I don't know when it was installed but I think it just supplies the garage as that is also wired in Pyro cable.Thanks for the comment.Merry Christmas and all the best for 2016 ;-)

[@cliffcarlo180]

I remember now, I think the company who made it were called Pyrotenax or something. The same as MICC cable used today to power smoke and fire alarms.

[@ultimatehandyman]

+Cliff Carlo Yeah, I think that's the stuff, although I'm no expert on it. I do know a couple of electricians that have installed it in the past and I think they said it was difficult and required special tools. Thanks for the comment ;-)

[@BariumCobaltNitrog3n]

I like your video a lot so I'll give you some numbers. Here are some rates for a northern california city, Oakland November 2017 at a pressure of between 45 and 80psi, plus a service charge based on pipe size $30, $90, $290 for 1" (25cm) 2" (50cm) 4" (100cm) per month. Rates for Single Family Residential Accounts (per 100 cubic feet) First 172 gallons per day (gpd) $3.45 All water used in excess of 172 gpd up to 393 gpd 4.74 All water used in excess of 393 gpd 6.27

[@ultimatehandyman]

Thanks for the comment ;-)

[@AlastairjCarruthers]

Pressure is how much force there is pushing the water along. Flow is the volume of water being moved. If you blast someone with a Super Soaker water pistol, the water will hit them with quite a lot of force, but the volume of water being delivered is actually quite low. This system is high pressure, low flow. If instead you tip a bucket of water over their head, they get lots of water on them in a short time, but with very little force behind it. This system is high flow, but low pressure.

[@ultimatehandyman]

👍

[@SeanHayesParleys]

Great title, but I still don't know the difference between pressure and flow. All I know is that I might need to add a reducer. On to the next video to learn the answer to my question. 👍

[@ultimatehandyman]

I need to add a pressure reducing valve here at some point!

[@bartender1222]

I've connected a pressure water test gauge to my garden hose tap and got a reading of 42 psi (2.5 bar) is that ok?

[@ultimatehandyman]

Not much you can do about it as there is no set minimum or maximum pressure- you just get what you are given by the utility company. Thanks for the comment

[@bartender1222]

Ultimate Handyman - And my final question, does the pressure remains the same all year round regardless of the temperature (weather)?

[@ultimatehandyman]

It should be roughly the same, but in colder weather the water can take longer to heat up, so for example you may see reduced flow on electric showers etc. Water pressure can also fluctuate depending on how many other houses are using water at the same time etc.

[@Diehard65]

It all depends on how much additional pressure is lost when flowing. What you're checking is STATIC pressure only. The critical pressure is the flowing pressure(Residual or Dynamic pressure).

[@BigEarlPearl1]

If I increase my PRV to a higher pressure will it increase flow rate?

[@ultimatehandyman]

No, that will increase the pressure. Is the main incoming stop tap fully open? I need to fit a PRV here as the pressure is way too high! Thanks for the comment 👍

[@tommymartin5555]

no problem

[@davidworsley7969]

Well,I suppose all the physics professors watching will not be surprised,but as a retired plumber,I certainly was.! It was however considered bad practice to reduce flow with a stoptap,I can't remember why-must have slept through that bit!

[@ultimatehandyman]

+David Worsley I really want to install a pressure reducing valve, but can't as the pipework is buried in walls- behind tiles.Hopefully when I replace the downstairs toilet I can cut out an access panel and install a PRV.Thanks for the comment

[@Theninjagecko]

+David Worsley If you use your stop taps to reduce your flow over time the rubber washer will get worn and may result in the tap now working when needed.

[@davidworsley7969]

Theninjagecko An interesting theory,but after considerable thought (my head is still hurting) I think it was due to a possibility of the loose jumper fluttering and causing noise also the exposed threads would be susceptible to build up of lime scale and grit,making it hard to open fully if required.

[@Theninjagecko]

I'm a network engineer for my local water company, I deal with all aspects of distribution and in home plumbing on cold water only. we advise not to throttle the flow with the taps because of causing problems with the lifespan of the tap. I've known cheap taps with fixed jumper to still rattle and cause a noise.

[@davidworsley7969]

Theninjagecko So I was on thr right track then?

[@yusuf.alajnabi]

if you wanted to increase your water pressure or flow rate per minute how would you go about doing that good video but the way ☺

[@ultimatehandyman]

+Yusuf Maltese Thanks, you can't increase the flow or pressure of the incoming main water supply (you can only reduce it). But if for example if you had a low flow rate and wanted to increase it for a shower etc. you could get a water storage tank and then pump it out from the tank.

[@crazylove2426]

Is the below statement true - Every high flow may result in high pressure of water but every high pressure may not result in high flow of water.

[@ultimatehandyman]

Yes

[@iwantosavemoney]

100 psi is crazy I have never seen that much most if them are around 60 psi give or take.

[@ultimatehandyman]

+iwantosavemoney Yes, it is very high.The incoming stop tap is normally only open a quarter of one turn!Thanks for the comment ;-)

[@EliteHydronics.]

ideal for unvented system !

[@ultimatehandyman]

We settled for a combi ;-) Thanks for the comment

[@MrAirsoftmodz]

we had magjor rework onout road for gas they put the shut off valves next to the water ones as the have covers. since then we have pathetic flow, we notice this mainly on the outside hose pipe as wee had a tank for heating and storage. the entire street has found the same thing but water company insists the pressure is correct for the street, but they wont help fix the problem. thanks for this demonstration I guess we have been barking about the wrong matter,

[@ultimatehandyman]

+nathan hellyer I don't think there is a minimum or maximum amount of water pressure or flow that they have to supply. I live in a pretty hilly area with reservoirs that are high up, but we also have pumping stations. High pressure is much easier to fix than low pressure, I'm not sure if there is anything that you can do about low pressure/flow to be honest. I can imagine it being very irritating though! Thanks for the comment ;-)

[@MrAirsoftmodz]

we have a pump on the hose so its usable now, when we brought it up they said that they had to lower pressures slightly because the chance of a leak or something, im also in a hilly area with reservoirs but instead our water is pumped up to us

[@ultimatehandyman]

+nathan hellyer Too much pressure is not a good thing as it can cause leaks etc. Thanks for the comments

[@Only-one-life-68]

@@MrAirsoftmodz Did you put in a external inline water pump on the inlet to your garden hose,or did you put the external pump were the mains water comes into your home.

[@simonroberts7309]

Ohm's law is for electric, what's the equivalent in water?

[@ultimatehandyman]

No Idea, sorry. Perhaps a scholar will answer 😂

[@muhammadwaheedriaz2570]

Sir what is the difference between Static and Residual Pressure?

[@ultimatehandyman]

Static pressure is demonstrated in this video, residual pressure would be the pressure in the system, if water was being drawn off at the same time. Thanks for the comment 👍

[@frazzle657]

I mean... I don't think this is correct... When you reduce the flow you are reducing the pressure by restricting the diameter through the valve. Same principle as running this tap through a really really long hose. You'd have a poor flow at the other end and equally much lower pressure wouldn't you? Or you are saying the pressure wouldn't change?

[@ultimatehandyman]

Think about a hose pipe, if you squeeze the end, the water will travel further.

[@vinceking7878]

Odd