Renovation of hot water system / and house ~ advice required

[phantom12345]

Hello.
First, if their is a forum I have not read were this is posted a link will be great and much apprechiated.

Like most problems it is conflicting advice and is confussing me.

I have a vaillant eco boiler (combi boiler). Currently linked to a hot water cylinder with expantion tank in loft.

My plumber is cool, and said its no problem to plumb it to use its full combi facilities. Then we can rip out the tank and cylinder to give us more space (just brought the house last month).

I have a combi at home, and when I have a shower and someone turns on the hot water ~ the presure drops and I get no hot water!

Is their a system I can install that will prevent this from happening? Is it possible to have a hot shower and someone else in the house use hot water, with out me freezing. (or two people having shower at same time).

My wife always says 'In france we have it so their is no loss in pressure ~ why not here? '.

Please help! I am renovating house before moving in ~ and its now or never to get it right.

Thanks for listening to my ignorance!

 

[simond]

Firstly, all Vaillant boilers of the last two years are called ECO. So this narrows it down to about 16 models.

If it is a combi that narrows it down to about 10.

Most ecoTEC combis cannot manage two showers at the same time apart from the 937, or its predecessor the aquaPLUS. These two could, but they would have to be standard 10l/m shower heads, nothing fancy, and that is only if your water main delivers in excess of 20l/m.

The only advice worth getting is that of a good installer who has measured the mains water, ascertained which combi you have, and asked you what your expectations/usage are.

If you are not asked these questions then your contractor either does not care or is not listening.

This type of question can never be successfully answered on an internet forum. It is like trying to knit a jumper through a keyhole.

 

[muggles]

Assuming your water supply is adequate, and your budget suits, you'd be much better off binning the combi and the HW cylinder and installing either a System Storage boiler or a system boiler and an unvented cylinder.

I am of course saying this on the assumption that your current combi won't cope with your requirements

 

[phantom12345]

Thankyou, I know the info wasn't top notch.

I don't know the water pressure ~ but will find out.
Will find out the exact model ~ I honestly didn't know their was so may variations of the same model of a make.

IN GENERAL, does an unvented cylinder provide more pressure to showers than a combi bolier acting alone?

I also noticed while working on my house that all pipes are 15 mm, hot cold and raditator. In the house that we are moving into the radiator main pipes are 22, but branch off on 15mm pipes to the actual ratiator.

Another builder (not plumber) said you can do this with the hot water supply and the pressure is better when two taps come on. Is this true.

Will get more info tonight.
Wife has still to make up her mind on all facilities (which makes it hard for me to build). But insists that hot water should be supplied to at least to exits (shower plus tap) without lossing pressure.

 

[phantom12345]

it is a eco vaillant 624 r1.
we are installing and under stair toilet with wash basin. Kitchen will have hot water for washing, plus dishwasher and washing machine.
Upstairs, bathroom. This bathroom will have a bath and shower together plus another washbasin.

Radiators = 7.

Latter update in 3 years loft conversion ( +10 radiators) and additional shower room.

IS IT BEST TO link combi boiler to an unvented system to increase pressure?

 

[Deleted member 105431]

it is a eco vaillant 624 r1.

this is a system boiler NOT a combi.

 

[gas4you]

Your plumber may be 'cool' but if he doesn't know the difference between a combi and a system boiler, I personally would look elsewhere for any work to be carried out

 

[phantom12345]

I will double check, it was a lable on the underside of the boiler ~ I am sure I got it right.
He did call and check with his partner! Strange because it has a dial for hot water temp and another for radiator.

Thankyou ~ for helping me out guys! (girls?!)

Can someone help me with, unvented cylinders. Do they provide more pressure than a combi boiler? (I have a combi in the house I am living in at the moment). My wife wants pressure!

 

[Deleted member 105431]

Your plumber may be 'cool' but if he doesn't know the difference between a combi and a system boiler, I personally would look elsewhere for any work to be carried out

ditto

 

[mickyg]

I will double check, it was a lable on the underside of the boiler ~ I am sure I got it right.
He did call and check with his partner! Strange because it has a dial for hot water temp and another for radiator.

Thankyou ~ for helping me out guys! (girls?!)

Can someone help me with, unvented cylinders. Do they provide more pressure than a combi boiler? (I have a combi in the house I am living in at the moment). My wife wants pressure!

all vaillant range boilers have a water temp dial, but unless you have a combi or have vaillant control system it does diddly squat.

combis are limited to a set flow rate, whereas unvented can provide an unlimited(within reason) flow rate, ie whatever you put in you will generally get out. I have an unvented cylinder that provides 32l/min, which will kick any combi into touch.
but not everyone is as fortunate as me to have such a good supply pressure
my general advice is upto 18l/min supply pressure go for combi, over 20l/min consider unvented.

 

[phantom12345]

is their a DIY way to get the flow rate without calling out a plumber?

It may sound silly, but just asking!
Is it based on water pressure or is it actual water flowing from the tap into a bucket? and seeing how much in a minute.

Can I call my local water supply company?

 

[gas4you]

Is it based on water pressure or is it actual water flowing from the tap into a bucket? and seeing how much in a minute.

Exactly, one way of doing it

 

[phantom12345]

thanks