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water pressure

Pressure (symbol: p or P) is the force applied perpendicular to the surface of an object per unit area over which that force is distributed.: 445  Gauge pressure (also spelled gage pressure) is the pressure relative to the ambient pressure.
Various units are used to express pressure. Some of these derive from a unit of force divided by a unit of area; the SI unit of pressure, the pascal (Pa), for example, is one newton per square metre (N/m2); similarly, the pound-force per square inch (psi) is the traditional unit of pressure in the imperial and U.S. customary systems. Pressure may also be expressed in terms of standard atmospheric pressure; the atmosphere (atm) is equal to this pressure, and the torr is defined as 1⁄760 of this. Manometric units such as the centimetre of water, millimetre of mercury, and inch of mercury are used to express pressures in terms of the height of column of a particular fluid in a manometer.

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  1. K

    Variable water pressure causing electric shower problem

    I have a B&B that has had lots of plumbing issues in the past e.g. hot water to a toilet! I am fed up of spending money so hoping someone can help as several plumbers so far have been hopeless. The latest problem is that I had an electric shower replaced because it was cycling between scalding...
  2. J

    Can you increase water pressure to your home?

    I have a unit (1 of 3), and mine is furtherest from the road. I have fairly crap water pressure and have had the water corp out, who agree its crap, but claim its due to the distance from the mains. Is there something that can be done to increase water pressure?
  3. A

    Do you have balance hot and cold water pressure with a combi boiler?

    So getting a digital shower and it says the hot and cold water should be balanced. Am I right in thinking they should already be balanced with the hot taking on the cold pressure entering the boiler or am I way off? Cheers
  4. F


  5. Grahampowell22

    Hot water pressure dropped on two outlets only (mega flow)

    Hi. We’ve a pressurized megaflow system and the last few weeks we’ve lost water pressure on Just two outlets in the house. The first a Keuco mixer shower were the hot outlets is just a dribble where previously it filled the bath in 5 mins and the second a Quooker tap where the tank fed supply...
  6. S

    Potterton Powermax with mains water problem

    I’ve been called out to a problem with a Potterton Powermax involved. The water pressure coming out of every tap dies off after around 30-50 secs. I took the multi-block off & pressure tested the mains where I have over 4 bar coming in. I changed the multi-block & although I have a slight...
  7. Bettyboo

    shower valves and change of water pressure?

    Hi All Thames Water recently came to fit an outside water meter and since then I have had two 1901 bristan shower cartridge/ valves dripping . Is it possible this was the cause ? When I did up the house I had a 25mm MDPE main water pipe fitted between the external stopcock to a new internal...
  8. A

    What amount of water pressure comes through a normal house ?

    Every time I use a stop end when I turn the water back on I think to my self that’s going to pop off and flood the house. What amount of pressure can they with stand ?
  9. N

    Digital or electric shower

    I need advice on whether I should get a digital or electric shower. The water pressure in my flat is very poor for the shower (gravity fed water system, heated via HIU, on a district heating system), I’m on the 3rd floor (top floor) so it’s to be expected. I know an electric shower would boost...
  10. D

    Mains Water Pressure Advice

    Hi all, My house is about 28 years old so some things are starting to fail with age. I changed the main water stopcock and well as the PRV as the stopcock was leaking and the pressure valve would not budge from 4 bar (even when it was disconnected). My main question is - what is the upper...
  11. A

    Replacement shower valve reduced water pressure -need to replace again

    Hi we had a Thermostatic Aqualisa shower valve upstairs that was tank fed upstairs in our house and it had great water pressure. We recently had our shower completely redone and the valve the plumber put in doesn't seem to be very good and the water now has very low pressure. We know the...
  12. J

    URGENT Installed Unvented cylinder will cause water pressure high?

    Dear all, I recently got a gas engineer installed a new boiler and an unvented cylinder & expansion vessel in my house, replaced the old boiler, vented cylinder and water tanks in loft. Just after a month of installation, last week, the house lost hot water, it was because the cylinder...
  13. R

    Combi Boiler Low hot water pressure

    I have I have an Ideal C35 boiler. We have really low water pressure from all the hot taps (should be getting 15 litres per min if using more then one stood completely). On Friday Ideal came out and changed the diverter valve, heat exchange and motor but it has made no difference. The cold...
  14. K

    low water pressure shower head

    I purchased HIX 250mm Fixed Shower Head 1 month ago (here is the link to the product HIX 250mm Fixed Shower Head - Brushed Brass Finish, MP 0.5 [33250BBR] - https://tapron.co.uk/products/gold-shower-heads-33250bbr from Tapron) 1 month ago but the water pressure is very low, can someone help me...
  15. S

    Oil boiler in low water pressure location. Pump problem.

    Hi, I have an oil boiler in a low water pressure location, ran well for 12 years, now I have a problem. And two questions. (1) I continually have to bleed air from the pump, can't work out why. Any ideas? (2) because of this, I am continually running down the pressure, which is already...
  16. P

    Water pressure

    Low water pressure in house. Ask authoroty to increase. Current 3/4" pipe leads into house. They go and install TWO 3/4" pipes (from main pipe in street) in my ONE pipe that goes to house in order to increase pressure. I dont see any improvement. Can 2 input pipes (instead of previous one)...
  17. K

    Hot water pressure- strange storage tank

    Hello. We have a system boiler in the kitchen filling what appears to be a two stage storage tank on the landing (under boiler pressure). There is no additional storage in the attic. Hot water from the shower bar is fine but all other hot taps are low pressure. Cold water pressure appears fine...
  18. A

    Very low hot water pressure in shower

    Hi there, I am facing an issue with very low hot water pressure in my upstairs shower. I have unvented hot water cylinder on the same floor and another shower as well. The hot water pressure is good in the other shower as well as in the bath mixer tap. I have a GROHE 1000 mixer shower and i...
  19. P

    Best option to reduce high water pressure - plumber and PRVs vs. water company?

    Hi (again!) Following on from this thread.... https://www.plumbersforums.net/threads/under-pressure-dum-d-d-dum-dum-options-for-high-water-pressure.122904/ I hope you don't mind but I thought I'd start a new one as Dwr Cymru could turn up next week so really want to decide what's best and...
  20. A

    Intec 34c hot water pressure low but boiler isn't.

    Hi everyone, I've got a strange one. My boiler (intec 34c combi) has good pressure (high end of green). When I open a hot water tap, the boiler fires up fine but it's just a trickle that comes out the tap. The water does get really hot though. My boiler is placed over an alpha flowsmart 50...