Increasing Hot Water Pressure

JoeShmoe_2

We've just moved into a new house in Edinburgh and we have really low hot water pressure in the bathroom and the shower room. Seems in the Kitchen the hot water pressure isnt too bad, nor do our neighbours indicate to us it may be a supply issue

As such im wondering if its a good idea to install a pump and what sort to go for. I understand the Stuart Turner Monsoon pumps come well recommended but im after some advice on which type to use

Clearly we want a pump that isnt specific to one device (i.e. a shower or a bath) but rather to all the applicances in the house. Im thinking a Stuart Turner Monsoon 2 bar single ended positive pump might be the one but would appreciate some help and also where best to install it (straight off the boiler?)

Cardew

I assume you have a hot water tank and not a combi boiler?

I have this problem - with a tank system - and consulted a plumber. He advised that the simplest way, if physically possible, was to raise the cold water header water tank. Even a couple of feet will apparently have quite an effect.

I did look at a pump, but have been advised that noise and vibration are almost impossible to supress. Judging by some houses I have seen with power showers, that might well be true.

With a combi boiler, none I have seen have the capacity to heat water fast enough!!

JoeShmoe_2

Yeah, its a combi boiler ... quite an old one too ..hence why Im wondering whether the pump will help

Cardew

The limitation on most(all?) combi boilers is they simply cannot heat enough water quick enough at even normal flow, especially when the input water is cold.
If you look at the spec sheets even for large modern combi boilers they will quote a specific flow rate when heating the water by 35C. So adding a pump I suspect will increase the flow of tepid water.

A BG heating heating told me that in the winter the commonest cause of call-outs were to Combis that just won't heat up enough water.

Loki_2

Hello
I'm new so forgive me if this has been answered elsewhere.
I work for a Water Company, and am often asked about issues with pressure and supplies.
It could quite simply be that the combi you have is not sufficient for the needs, like having a 1.2cc engine in a luton van, loading it up and expect it to lug around the load with ease when really a bigger diesel engine will do the job with ease but will need to for fork out more.
Also if you don't have good pressure to start with, generally if you are on a common / shared supply it is not the best design and a traditional system may be better.
I have a combi that is over 10 years old in a 3 bed semi and I can shower from that upstairs with ease and the pressure to my house is adaquate (for someone who works in the industry) I also had one in a previous house and that worked fine but was told to have a single supply to the house before one could be installed.
The key will be down to the design and a good plumber, which can be hard to find if one is not recommended.
Also if you go to BG, they (or there contractors) have frame work agreements with manufacturers and will only supply them unless requested.
Hope this is of help
Loki

CrazeUK

Hello all, firstly thanks in advance.
I have just moved into a new house which is about 9 years old.

It has a normal boiler with tank which is a Potterton 50F.
Their are 3 bedrooms, a kitchen 2 bathrooms and a lounge.

My problem at the moment is hot water.
In the bathroom we just about manage a trikle of hot water from the shower, barely sufficient to wash you. In the kitchen the pressure is a bit higher, but still low.

After a centeral heating engineer came out for a seperate issue, he suggested their was a cold water feed pipe to the water tank which was at the wrong angle, I got that changed but with no affect.

I initially considered installing a Electric shower, but am reconsidering seen as the pressure to thekitchen will still be low.

I have considered a combi boiler, but at an estimated £1800 it wont be something i can invest in for a few years.

Does anyone have any suggestions?

Me

John_3:16

We had this problem and I wanted to get rid of the electric shower as having to growing boys they just stood under it for 20mins at a time. When we change the bathroom around my first job was to raise the tank by about a mtr it has given us a lttle more head of water that has made all the differance. In the summer the pressure is possibly not as great as the mains electric but in the winter it is good as you can have the water as hot as you want without loss of pressure. My advice is if at all possible raise the tank. I would say there is a about 1 1/2 mtres frm the bottom of the tank to the shower head. I asume if you have a bigger tank header tank the pressure will be greater?

MarkyMarkD

As Cardew says, the problem is that combi boilers are basically rubbish and won't deliver sufficient flow of hot water in many cases. Obviously they are even worse in the winter when the supply temperature is colder.

CrazeUK - your problem certainly won't get better by getting a combi boiler. What you need is to sort out the flow into your cold water tank, as your first engineer said. I'm not sure I believe that the angle of the pipe is the issue - but it certainly sounds like the problem is somewhere between the main water feed into the house and the cold water tank.

John 3:16 - I don't think that the size of the header tank is relevant. Pressure is proportionate to height, not to size of tank. But raising the tank as you did is probably worthwhile in some circumstances.

John_3:16

When I said bigger I asume this would also take into account the height.

Here is a question for you.

If you had a header tank 6inch square 1mtr high would it have the same pressure as a tank 3mter square with water 1mtr high?
I just wonder if volume came into it?

We also made sure that we had 22mm pipe to the shower so flow was not reduced

MarkyMarkD

Yes.

Pressure = h [SIZE=-1]ρ [/SIZE]g where h = height [SIZE=-1]ρ[/SIZE] = density and g = gravity.

The size of the container doesn't make any difference.

But a header tank as small as you suggest would be likely to run out of water and then you'd have no pressure at all!

John_3:16

Are we missing a trick here. We should manufacture long thin header tanks. You will get them in the loft easy and the pressure will be better. The mains pressure should always be up to filling it up!