Low (and decreasing with use) water pressure

[Sway]

We've started experiencing some very odd things - when running a bath as an example, it'll start off just fine, then pressure on both hot and cold (hot first) starts reducing. Last night, to the point it was dripping not flowing.

Same occurs if just the cold tap is run.

We've noticed this often coincides with afternoon/evening, and when the pressure 'comes back' we've noticed spurting and gurgling (under good pressure) from cold taps and loo filling points.

Broader system - three storey house, combi boiler and megaflow tank, stupidly hard water area (South Coast) served by Portsmouth Water (drainage is Southern Water).

Any hints or advice? Tried the stopcock as advised by water Co website. No change.

[bunchofkeys]

Leaks in the pipes further up the street or another part of the pipe network, which affects you. Take a look at your suppliers website to see if there have been any recent reports of leaks or maintenance works.

[Sway]

bunchofkeys said:

Leaks in the pipes further up the street or another part of the pipe network, which affects you. Take a look at your suppliers website to see if there have been any recent reports of leaks or maintenance works.

Thanks, did wonder if it was an external issue.

Supplier states nothing locally, however Mrs Sway has just logged an issue with them.

[miroku1]

What type of incoming main pipework do you have ? Mdpe , galv or lead ? If it’s not mdpe get it replaced . Do you have prv on the incoming main ? Stop tap ok ?

[Sway]

miroku1 said:

What type of incoming main pipework do you have ? Mdpe , galv or lead ? If it s not mdpe get it replaced . Do you have prv on the incoming main ? Stop tap ok ?

Pass on the first few - how would I check?

Stop tap seems absolutely fine, closed/opened a number of times with cold tap on. Switched water off and back up to previous pressure no issue.

[Magic919]

It’s not usual to have a combi boiler and a hot water cylinder.

Presumably the Megaflo is running unvented. It’ll have devices to manage water pressure and provide balanced cold. Get someone qualified in to look at it.

[OutInTheShed]

Magic919 said:

It s not usual to have a combi boiler and a hot water cylinder.

Presumably the Megaflo is running unvented. It ll have devices to manage water pressure and provide balanced cold. Get someone qualified in to look at it.

This!
There could be a pressure regulating valve on the supply to the whole house or boiler.

First thing to do is check whether neighbours are having similar.
And then that all the stopcocks are turned fully on.
A mate found that the meter stopcock was dodgy, it looked to be fully 'on' but wasn't!

[Sway]

Magic919 said:

It s not usual to have a combi boiler and a hot water cylinder.

Presumably the Megaflo is running unvented. It ll have devices to manage water pressure and provide balanced cold. Get someone qualified in to look at it.

I believe it is unvented. I think it's a combi!

It's a Worcester greenstar RI, with Megaflo on the first floor.

Does that mean it could be my setup failing in some way that's also affecting the cold feed?

[Magic919]

A Greenstar Ri is a heat only boiler, not a combi.

It’s possible if the outlets you test are a balanced cold supply.

[530dTPhil]

I had low water pressure on a Megaflo system and eventually tracked down a pressure regulator on the supply to the hot and cold. I had no idea that the device was fitted to our set up. Apparently the filter is supposed to be changed every three to five years; ours hadn't been done in the the ten years we had been in the house.
Ours had been superceded several years ago so we had a new one fitted; result, we had better water pressure than we had ever had. Took the old unit apart and found that the main spring had broken in two.