I have a plumbing question, piglet?

[Giddypants]

We have serums lay bad hot water pressure in the entire house, (takes about 20 minutes to run a bath 20 cm deep) at present we have a water tank in the attic, cylinder in the airing cupboard and a boiler in the garage.
The whole system except the boiler is about 22 years old (boiler 2 years) the cylinder has just started leaking at the bottom, and we have asked a plumber if we could fit a pump to sort out the hot water pressure and replace the cylinder. He said pumping the whole house not a good idea, and probably our best option would be to remove the cylinder and fit a combi boiler.
We have been quoted to fit an ideal or Worcester Bosch boiler, which one is best? Would it sort out the hot water pressure problem? Would we still need a tank in the attic?
Or is it advise able to pump the whole house?
TIA

Worcester Bosch and Vaillant are generally considered to be good boilers, Ideal not so much.

The drawback of a combi boiler is that you can't get get water out of the taps faster than the incoming water main delivers it. Run your cold kitchen or garden tap into a bucket and time it, calculate how many litres per minute you get. An ordinary combi will not be satisfactoy if you have more than one bathroom or shower in use at the same time.

How old is the house, and what colour is the incoming water pipe when it comes to your stopcock?

Pumping the whole house will be noisy.
if your boiler is only 2 years old, it seems wasteful to chuck it in the skip.

How high is the cold water tank in the loft, above the bath tap?

Is it a modern, flashy stylish italian mixer tap, perhaps with a ceramic discs and a joystick? When you fill your bucket, how many litres per minute does it deliver? how about the basin taps?

I think you should get in a couple more heating experts to look at your system and advice.
As piglet say - seems a waste to chuck out a newish boiler.
Answer all those questions asked by piglet.

You need good water pressure coming into your house for a combi.
Even if you have good incoming water pressure
AND
a good combi -
There are various disadvantages to combis - one of which is that they are slow for running a bath - although a bit faster than what you are currently getting.

We thought that about the boiler too.
The house is 22 years old but was re possessed and 'done up' (I use the term loosely) 2 years ago before we bought it, according to the local plumber when they refitted the bathroom, en suit shower and kitchen they extended the pipe work which is why there is no pressure.
I can only see a copper pipe coming in where the stop cock is.
I've worked out that we would roughly get about 144 l/min does that sound about right, I think the plumber also said that the cold water has been limited as it was quite a high pressure, and no problem with the cold water pressure.
The rooms are standard height (no high ceilings etc) so is that 8ft ish? the tank is about9 ft away from the bath.

we fitted a new bath and mixer tap about a year ago as dh was moaning he couldn't fit in the standard size one and fitted mixer taps which very slightly improved the water pressure but not much.
There is only me and dh who would use the shower and the kids have a bath on a night so very rarely would both be run together.
Dh says that it's a gravity fed system with a max 4ft fall, if that makes sense to you? it doesn't to me

no, it won't be 144litres per min.

It might be 14, but measure it and see.

4ft head is not much.

It would be possible to double that by building a wooden platform in the loft reasonably easy.

The pipes from the tank to the cylinder, and the cylinder to the bath tap, should be 22mm diameter, as should the separate pipe from the tank to the bath cold tap (not 15mm which is the size of a finger). Look for any stopcocks or service valves on these pipes, which will restrict flow.

A good big 22mm pipe and a British tap will get plenty of flow even with a 4ft head. I was asking about the basin flow because if it is a pillar tap, not an imported mixer, it may be quite good.

if you do decide to get a new cylinder, get the biggest that will fit (they usually contain about 120 litres, which is enough for a good bath) and have the pipes replaced if they are not 22mm.

I am suspicious to hear the cold water has been restricted. This is often a bodge when a high-pressure cold supply is (wrongly) connected to the same mixer or shower as low-pressure hot.

As well as 22mm pipes, a UK-standard 3/4" Pillar Tap like this Bristan will give the best flow you can get. UK water supply is not the same as most European or US methods, so the plumbing and taps need to be different. Modern designs are also available if your taste differs from mine.

p.s.

if the house is only 22 years old, there is a good chance that the incoming watermain will be black or blue plastic. If so it may have had the 15mm copper put onto it where it first comes into the house, usually where it rises through a concrete floor near the sink. if so, and you can get at it (maybe the kitchen fitters hid it under a cupboard) there is a good chance you could put 22mm stopcock and pipe onto it which will improve the flow, very important if you decide to go for a combi.

My own preference would be to keep a tank, cylinder and boiler installation, but improve the water flow by removing obstructions which are likely to be caused by 15mm pipes and stopcocks. An older plumber will be very familiar with all this, and it does not involve any boiler work so you do not need a gas installer.

I ran 10 l in 24 seconds so about 16 l / min, math isn't my strong point!

(10/24)*60= 25lpm which is a lot. Can you check that please? use a bucket or washing-up bowl.

Is that at your kitchen cold tap? is it a mixer?

please try the cold and hot tap in the bathroom as well.

Dh says. The tank is already on a platform and can't be high ered any more.
We have all mixer taps in the bathroom. The basin is on a pilar, dh also says that the cold water feed is on a 22mm and hot water 15 mm onto a flexible coupling and the cold water pipe near the stopcock is blue. (He's just laid new floor in the kitchen)
I forgot to mention that the cylinder has started leaking at the bottom, the first plumber said it would need replacing

Right I rechecked the water.
In the kitchen, mixer tap cold water I ran 6l in 15 seconds so 24l/min
In the bath mixer tap I ran 3.5 l in 15 seconds from the cold tap so 14l/min
And in the hot bath tap I ran 750mls in 15 seconds so 3l/min
Dh said that the stopcock in the kitchen is not fully turned on and therefore has a restricted flow

If the hot water supply is on 15mm, that will explain why the bath takes so long to fill. I expect you mean one of these. not only is the hose inside the braid smaller than 15mm, they usually have a ball-o-fix type stopvalve at one end, operated with a screwdriver, and the hole in this is even smaller, so very restricting.

They do make it easy to fit taps, but if you can, swap it for a 22mm version and use a 15mm reducer to connect it to the copper pipe, I think you will find that makes an immediate improvement. The bath tap should have a 3/4" thread on the tail that the flexible connector will screw on to. This is a quicker job than running new 22mm pipe, which I also recommend.

I'm pleased to hear you have a blue plastic pipe, it will be either a bit or a lot bigger than the 15mm copper, so this will be a good place to fit a bigger stopcock and start running new larger pipe if and when you go for a combi or a Megaflo. A Megaflo is a type of high-pressure cylinder (other brands are available) and can be fed at mains water pressure, without neeeding a loft tank, and heated by your existing boiler.

If your cold water flow is as good as it seems, that would probably be your best option. It is likely to give superior flow and pressure, better than a combi.

The high-pressure cylinders have to be installed and serviced by a person with an extra qualification, not all plumbers and heating engineers will have it.

Do an "Advanced Search" on "Megaflo" and see what you think.

p.s.

In the bath mixer tap I ran 3.5 l in 15 seconds from the cold tap so 14l/min
And in the hot bath tap I ran 750mls in 15 seconds so 3l/min

this tells me that your bath mixer is fed with high-pressure cold and low-pressure hot. This is very bad practice for a mixer and often leads to leaks, it also makes it almost impossible to adjust the mixer for blended warm water.

Thanks pigletjonn I shall let dh know he's been called out to work, and will be back early hours x