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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. B

    Rain/drench shower pressure

    I’ve been asked to install a rain/drench shower head. I know these can be issue with low pressure. Mains at garden tap is 1.5bar, combi boiler in loft about 5m up, then shower on second floor so below the combi. I’m thinking this is 1 bar at the outlet and should be a good pressure for a 250mm...
  2. M

    Pressure booster - dripping sound

    I have a Grundfos Home Booster 3.0 in my rental property. Was installed 3 years ago, I've never been at the house since it was installed and nothing was every reported to me by tenants so don't know if this has been the case since day 1 or an issue.... ..but I hear a constant slow drip from...
  3. J

    Low hot water pressure

    I've had a new Firebird combi oil boiler fitted and the hot water pressure is low( in fact it's terrible)..the cold water pressure is good and I can't find any leaks and loose no pressure. Please help. Thanks alot
  4. G

    Cistern fill valve - very low pressure

    Hello, does anyone know of a side fill valve that works in very low pressure situations? I installed two separate new side fill valves on my concealed cistern today, a Fluidmaster and a Dudley, both didn't seal properly. From reading reviews and forums it looks like it's due to the very low...
  5. P

    Gas regulator pressure affect bills?

    We’ve just had our gas regulator changed. Engineer told us our pressure was 10x what it should be. House is 20yo. Would this affect our bills?
  6. A

    Worcester Bosch Greenstar 30 CDi - Pressure loss

    Hi all, Recently moved into a new house and noticed the Greenstar boiler has low pressure on the dial. Quick Google suggests using a key, valves, or fill loop to increase the pressure. Only problem being is I don't have either of those things. Any help would be appreciated. Cheers.
  7. P

    NIBE ASHP Alarm 'low pressure warning

    Nibe ASHP alarm code 005 low pressure warning, anyone know the cause?
  8. P

    Navien 240E Pressure Valve Discharge

    Hey all, Not a plumber - know just enough to be dangerous.. We just changed our water filters out in the house, and ever since our combo Navien 240e is discharging small amounts of water all day out the boiler side pressure valve. Boiler is off with summer (still using hot water side), but...
  9. R

    Megaflow pressure high. Leaking from overflow pipe when water heating

    Hi folks. I've noticed recently that water is dripping from my Megaflow overflow pipe outside coinciding with the time the heating turns on to heat the water. Whilst the water is dripping, the pressure on the Megaflow is reading around 8 bar. Dripping from overflow stops and the pressure...
  10. B

    Very hot water with low pressure

    Hi we've just had a bathroom fitted with a mixer tap to the sink and mixer tap with a bath handheld shower fitting to the bath and there is almost no pressure at all. Previously we had single taps and the pressure was fine and is good downstairs. It is all gravity fed. We have a shower pump...
  11. B

    Insufficient water pressure for Trition 30i - Instant water heater

    Hello, I've had one of these plumbed and wired (3KW) in to my mothers house in order to add hot water to a sink with cold tap only (ex council 60') only to be told that the available water (to the Triton 30i instant hot water heater) is coming via the main water tank not mains pressure as...
  12. G

    Water filtration system in high rise apartment?

    We live in a high rise on the 18th floor. I want to have a under the sink water filter installed. Waterdrop 10UA Under Sink Water Filter System, NSF/ANSI 42 Certified, Under Counter Water Filter Direct Connect to Kitchen Faucet, 8K Gallons High Chlorine Reduction Capacity, USA Tech...
  13. Orchid_2022

    High Pressure Commercial Toilet

    I am looking for suggestions /advice on getting a commercial high pressure toilets that does the job in one flush. Does anyone have any toilets they can recommend?
  14. Arelia

    Water pressure in British homes

    Good morning, Can anyone tell me what water pressure British homes have? Thx in advance
  15. beccabeyond

    Shower pump for kitchen tap?

    Can I run a line from my shower pump to my hot water kitchen tap to increase the pressure? If yes, would I call a plumber or electrician?
  16. B

    Water pressure in kitchen unbalanced query

    Hi everyone, I have a question about balanced water pressure in my kitchen. Are both the hot and cold water pressure meant to be the same, as my hot water has good pressure when fully open but the cold tap pressure has about 2-3 times more pressure when the tap is fully open almost floods the...
  17. S

    Closed loop pressure increasing

    Just wondering if anyone has even seen an issue with the pressure gradually increasing on a closed loop system where there is no fill loop attached. I'm seeing this issue on a gshp and whats more unusual is its on the cooling side. If it was on the heating side you could put it down to expansion...
  18. E

    What boiler pressure loss is ok over time?

    My Ideal boiler pressure gauge pointer shows about 0.85 when cold (about 1.8 when the heating is on). 10 weeks ago the readings were 1.0 when cold and 2.0 when hot. Clearly there is a loss in pressure over time. I can see no leak on any radiator or near the boiler. Is this pressure drop of...
  19. M

    Pressure reducing valve - can I remove?

    As part of full house renovation, I've switched from a conventional boiler/gravity fed tank to a combi boiler. Under the old system I note that a pressure reducing valve has been fitted to the pipework feeding the shower mixer (assuming as mains cold overpowering the supply pressure from the...
  20. M

    Poor flow and pressure issues?

    Hi guys. I replaced an electric shower for a family member recently and on completion noticed how poor the pressure was. It wasn’t like this the week before when I initially looked at it. Apparently Severn Trent were in the area the following week to do some work. She’s now saying that the...