Pressure problems with my shower All aspects of plumbing questions and answers, help, tips and information

[kkirkhope]

I have a Gainsbourgh RE600 which either produces scorching hot water or doesn't heat the water at all.

This is due to low pressure. I have had problems with it before but it has always eventually started working again properly.

I've taken the shower apart and there are no blockages in it or the pipe leading up to it.

The shower doesn't have its own dedicated pipe from the cold water tank the tank is three floors above me in my upstairs neighbour's attic (I live in a maisonette, a two storey house that has a two storey flat above it) and it would cause to much disruption to get a new pipe down. The pipe to the shower is 10mm in diameter and it comes of the supply that goes to the cold tap for the bath which in turn comes of the main supply for the house with is the normal size (20mm?) of water pipe. I got 1.6l of water from the pipe that supplies the shower in a minute.

Scottish water replaced the mains to my street a year ago which filled my water tank with lots of mud and water which I think has clogged my water pipe.

Does anyone know how I can check pipes aren't blocked or if my water pressure I am getting in my flat is what you’d expect for in my circumstances please? I can't afford a plumber or any expensive equipment.

I can stop the water coming out of any of my taps (yip even the kitchen tap is fed from the cold water tank) with my thumb and not feel any pressure on it. Is this right if my water tank is about 8 metres above me?


Hope someone can help me as my shower is driving me mad but I don't want to replace it if the new shower will suffer the same problems due to low pressure. Ideally I’d like to replace it with the Mira Sport Max so I get hot water from the shower during the cold Scottish winters.


Thanking you in advance,

Keith

[DONFRAMAC]

The high- pressure rising-main water is the only safe drinking water. It is also the required feed for electric showers, unless you choose pump-assist.
You should T-off from the riser, using the same size pipe, to feed your cold taps & shower, and only use water from the loft tank for feeding your hot-tank ;-- it is not fit for putting in your mouth!
Lids are now fitted to these tanks, but this has not always been the case. Contamination by pigeon and rat/mouse droppings was once a recognised problem. Bats and birds are known to inhabit lofts, also bees, wasps, etc.

[kkirkhope]

Thanks for your reply.

Unfortunately the flat wasn't built with a riser so I have no choice in where my water comes from. The tank was replaced four years ago and is covered, I last inspected it a couple of months ago. Obiously if I could I would change the plumbing configuration if I could but I cannot at the moment.

Do you know the best way of checking if a partial blockage of my pipes is reducing my water pressure?

Thanks

Keith

[DONFRAMAC]

Your 8 metre pressure-head from your loft tank equates to 11.9 PSI.
The rising-main is usually 40 PSI, which is what an electric shower is normally fed from, using 15 mm copper pipe. So, your pipe is under-size, and the pressure-head is 1/4 the min. riser-pressure. I would suggest you drain and clean the loft header-tank, uprate the piping to your shower to 22 mm, stepped-down at the input to the shower to its max. input size.
Also, because of your fluctuating supply pressure due to outside influences it would be advisable to use a single-impeller shower pump, eg, hidden in a nearby cupboard. In my own home, I am fortunate in having my hot-tank thro' the wall from my shower, so that is where I put my twin-impeller pump for my blender shower. Unfortunately I did not spend enough on the pump. It was not continuously-rated, and siezed after a year of 3-showers in a row, every day.
Now, with 2 x 15 mm supply pipes, from the static-head, just 3 PSI is producing an adequate flow ;-- but I have boosted the hot tank temperature to 65 C.

[kkirkhope]

Thanks for your help.

I'll ask my neighbour if I can get into her attic to clean my tank.

Do you know how I can test the pressure I get from my tap to ensure its actually 11.9 psi?

[DONFRAMAC]

The 11.9 psi water pressure figure, is what I calculated from your 8 metre figure of height from loft tank inlet, to shower-head.
Way back in High-School, I learnt that one atmosphere of pressure equals 14.5 psi, also equals 760 mm ht of mercury in a barometer, also equals 32 feet of water-gauge. That explains why suction-pumps cannot pull water up out of wells that are deeper than 32 feet ;-- the pump has to be lowered down the well, or a fully submersible pump dunked in the well, but the output pressure needs to have enough oomph to get the water up to above ground. Very deep wells/mines sometimes use a daisy-chain of pumps to get water out.
Your local Garage or Car Enthusiast Club will have pressure gauge equipment, as they assess the condition of engines by measuring the compression produced by the engine, when spun by the starter-motor. The dial-gauge/hose/adaptor screws into a spark-plug hole, and the leads to the other spark-plugs are removed (or the plugs are removed).
You just need to borrow a compression gauge kit, or hire one from a tool-hire firm, and connect to your taps with garden hose fittings, then open the tap.
It would be worth seeing how much the pressure drops when you open other taps.

[DONFRAMAC]

The sport max shower you quote, I have checked on, is for rising-main pressure-feed. But the same firm make several high-flow pump-assist electric showers, to satisfy anyones needs. !6 litres/min, and a rose which can be gentle, and flow varied.
Go onto the website and get the full catalogue & price list as I just did, as I need a blender shower to suit a combi boiler -- they do 2 ranges.
Your 10 mm copper piping is one hell of a flow restriction --- has to be improved, whatever other decision you make.
A 10 mm pipe to/from a radiator can only suit a 1.5 KW radiator!!