Internal water pressure problem

I got an internal water pressure problem.
Its reading around 0.2 bars whereas external its 3 bars (water company proved it with their meters).
How does one attack this problem? (My very good plumber away till January).
All the stock cocks and other gadgetry is open and working.
What DIY tips and tricks can I use to locate the problem?
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7 wrote:

enormous leak which would be obvious). Or a faulty gauge??
Blockages, part open stopcocks etc do NOT affect pressure only flow.
Bob
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Bob Minchin wrote:

The gauge belonged to the water company and their engineer was very helpful in showing me measurement at street and measurement in house.

Arrr... that bit I forget!!! Thanks for that tip!!!!
I might be mistaking pressure and flow in previous post.
Flow is good in the cellar - but rubbish two floors up. The pressure is also low about 0.2 bars two floors up.
I can't seem to trace the path the pipes take - numerous amount of work seems to have gone in over the years. In some places there are service valves when they should be stop cocks and vice versa. Its hideous. I want to get rid of it all and have once central 22mm pipe going up the side of the house and all other taps from that main branch through 15mm pipe. Is that good idea?
But immediate problem is to find this pressure/flow problem.
I ordered a pressure meter which will arrive later this week mail and weather permitting, to note pressure at every tap in the house to see if that will shed light. I also ordered a cheap endoscope type USB camera to see if I can see anything under the floor boards without ripping them up.
What is best way to trace pipe routes? I can't see where they go when they dive under floor boards and into walls. Nothing is straight or lined up to make educated guess. Some of this piping must be more than 50 years old.
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the taps, as this would give lower pressure readings to the taps closer to the tank.
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Harry Stottle wrote:

There is a storage tank in the loft - but that gives out the cold water. That seems OK with plenty of flow. The gas heated hot water is connected directly to the mains supply or so I am told and its lost pressure.
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7 wrote:

measuring supplies from gravity fed tank in the loft. Prove this by either turning off the output from the tank, or seeing which taps in the house cause the tank ball valve to open and refill the tank. Work logically, one tap at a time and write down your results for each tap. Then you can start to build up a diagram of your plumbing system identifying which taps are truly mains pressure and which are gravity fed and which are hot and cold.
Mains pressure hot water is a relatively modern thing compared with 50 year old plumbing and either associated with a combi boiler OR a special hot water tank designed for the pressure which should have gauges and pressure relief valves. overflow tundish and maybe a regulator. All together more complex and pretty obvious. I think also that these latter systems have to have annual inspection so there might well be a record card of that.
Also either system for mains pressure hot water would have no need for a header tank in the loft. Even if an installer had not bother to remove it, he should at least have drained it and cut off its supply.
Work out just what system you do have and if that has not solved your problems, come back here armed with a description and diagram of what you do have.
We should be able to help then.
Bob
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Bob Minchin wrote:

A plumber came in today, undid a few pipes and got a glimpse of which section of which section had problems. Then undid another section blasted air through each branch and then filled every branch with water one at a time.
That worked.
It is possible some debris got stuck - but most likely he said the vast numbers of elbow joints had created areas where pockets of air could get trapped and that gives the impression of a blockage.
New problem then appeared: A hidden branch full of air was thereafter causing the gas heater to shut down late because when the tap is turned off, the flow of water does not stop until the air gets compressed and then slowly it stops - by which time the gas heater groans with pressure.
When that branch got filled with water as well properly through all the elbow joints, the problem stopped.
Definitely job for expert plumber.
Moral of the story - don't put too many elbow joints in your piping system - bend and curve the pipes smoothly for as many as possible pathways.
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< snip >

You obviously found one - they're a rare breed so don't lose his phone number :-))
--
martin


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