why do homes need water header tanks?

[bengasman]

Admittedly not something I have looked into too deeply, but I reckon that either the freeholder or the watersupplier has an obligation to the leaseholder to supply services up to spec, dito for a house that is far from the road.

Would I be far wrong guessing that the watercompany did not refuse to solve the problem in writing?

3 bathrooms? Don't see a problem there.

 

[bengasman]

BTW if you were installing the hot and cold water system in a large new build with ample head height with say 4 showers , two bathrooms , utility room and kitchen and the mains flowrate is measured at 14/L minute with no hope of upgrading what system would you propose?

And the question goes to Bangasman.

Unless it is a trick question where I missed the trap, it seems a really easy one.

I would propose to get the installer of the water connection back and ask him why he made the incoming mains for a large house in 12 mm in stead of 35. It is a nonsense question, because if I were responsible for the proper working of plumbing and heating, I would make sure the incoming water was up to spec.
I have never seen even a 1 bed flat with a maximum flow of 14 l/min, let alone a large house. The location is England, not Fantasia or Africa.

Maybe I should have specified that I am thinking along the lines or reality and legal installations.
Building a 4 bath/2shower house with a 14 litre per minute maximum flow is not legal, nor have you actually seen one in this century.

 

[Norcon]

with no hope of upgrading

Don't you know what this means?

 

[bengasman]

Don't you know what this means?

Not in this case.

You did mention NEW BUILT in which case 14 l/min does not meet the spec for a house that size.
It is not a matter or HOPE, but of enforceable obligation; not my problem if it is inconvenient, expensive, difficult or whatever.

Like the compulsory condensing boilers on new built, it is not my problem how much extra time, money or effort it takes to comply.
You did ask what I would do; I would make sure it is up to spec from the start, rather than implement second rate solutions.

Not being funny, I would be very interested in knowing about any situation that you described that really exists and find out what happened; always good to be able to come up with a precedent.[/b]

 

[Norcon]

not my problem if it is inconvenient, expensive, difficult or whatever

Thats a carp attitude to have IMO.
So you cannot offer a solution to the client.
But instead insist on options that suit your blinkered mindset.

 

[Onetap]

The reward was drink as much as you want/can for the evening/night.

The offer still stands.
Either there are no proper drinkers on this forum, or they don't like their drinks payed for by me.

Just so you know; the arguments "we have always done it that way" and " it is cheaper than doing it properly" don't cut ice for me.

I've just looked at this thread, I've missed out here.

The reason why storage tanks were adopted was because the mains supply was originally intermittent or low pressure. The water could trickle into the storage tank through, typically, a 1/2" service pipe, but there would be sufficient stored water to supply adequate flow rate to all appliances. The storage tank with one mains-fed tap was mandatory under the Water Regulations until 1987 (I think) when the Regulations were changed to allow the use of EU manufactured systems and fittings in the UK.

The main advantage of a storage tank system nowadays is that they have a type A air gap and are far more resistant to backflow contamination of the mains water supply. The loft storage tank was not favoured in the US or Europe because they have serious winters and the tanks are more liable to freeze. They also have a serious history of mains contamination. I used to have a link to a site with some seriously stomach churning incidents of mains contamination, but I've lost it. Have a Google for the Holy Cross football team ( US, most contracted hepatitis due to back siphoned urine from sprinkler pits during a major fire in a nearby town). Or the 'morticians' who used a venturi vacuum pump powered by mains water during the embalming process. The neighbors complained about the red-tinted water coming out of their taps.

A properly installed, insulated and maintained storage tank will not get contaminated. I will drink the water from my tank, because I know it is clean. I'd never drink water from any other storage tank.

A storage tank with adequately sized pipework will supply a generous flow rate to every appliance, except maybe a shower. Many mains-fed systems (combis and unvented storage) are incapable of supplying an adequate flow rate to a bath. The mains supply pressure is inadequate for many high-rise buldings.

I think unvented storage cylinders are a fad that are over-promoted by the manufacturer's advertising. They have their uses. I do have an unvented ticket.

 

[bengasman]

Thats a carp attitude to have IMO.

To insist that the installer comes back to do it right is a poor attitude?How odd. I would say that proposing a poor stopgap remedy, in stead of solving the problem of an illegal situation and changing it to a compliant one would be a cowboy attitude.

And in real life it would not have happened in the first place, as I would have been responsible for the plumbing and heating, which would mean it would have been 1 size larger than really necessary to allow for future expansion, and installed meeting all the regs, which a 14 l/min for a new built clearly isn't.

So you cannot offer a solution to the client.

I would not need to offer a solution for a problem, as I would not have allowed the cowboy installation in the first place. Prevention is far better than a cure.

But instead insist on options that suit your blinkered mindset.

It has nothing to do with what suits my mind set. Meeting the building regs requirements is a legal obligation; not doing so as in your (hypothetical and unrealistic) example, is a criminal offense.

Let me remind you what I said about demonstrable advantages of vented.

In England
Realistic/existing
Reasonable example
Legal

The situation you are describing is neither existing, nor legal.

As an installer, you have a legal duty of care. Amongst other things, that means you must install to spec, endeavor to upgrade illegal installations to safe standards.

Rather than trying to offend me, do something useful and describe an existing situation or project taking place where a vented installation is better than mains pressured.
It is not that difficult, here is one.

Client lives in such an isolated location that there is no possibility to connect to watermains without crossing a river or mountain range.
The household water comes from a well and collecting rainwater, which is then treated and stored.

Sorry, I forgot for a moment, I specified reasonable.

 

[fatplumber]

I can show you an installation within 500m of a major housing estate in Brighton. The undertaking says that they will not improve the supply.

 

[Norcon]

I would not need to offer a solution for a problem, as I would not have allowed the cowboy installation in the first place

You are asked to install a hot and cold water system in a property.
It's a new build with 4 showers , two bathrooms , utility room and kitchen. Their is ample head height.
With no hope of upgrading the mains supply.
The flowrate is 14/lmin.

What system do you propose?
Or do you walk away?

 

[bengasman]

I've just looked at this thread, I've missed out here.

The offer still stands

The reason why storage tanks were adopted was because the mains supply was originally intermittent or low pressure.

The offer is limited to NEW installations, TODAY; not 50 years ago, I don't care what happened in the past.

The main advantage of a storage tank system nowadays is that they have a type A air gap and are far more resistant to backflow contamination of the mains water supply.

Not needed if the plumbing is installed to spec in which case no contamination will take place.

A properly installed, insulated and maintained storage tank will not get contaminated. I will drink the water from my tank, because I know it is clean. I'd never drink water from any other storage tank.

A vented system is by definition open to bacteria, water may be crystal clear, it could be lethal, just the same as "clean" air could be toxic as hell.

A storage tank with adequately sized pipework will supply a generous flow rate to every appliance, except maybe a shower.

A mains system with the same size pipes will provide more litres per minute.

Many mains-fed systems (combis and unvented storage) are incapable of supplying an adequate flow rate to a bath.

Because the pipes are undersized.

The mains supply pressure is inadequate for many high-rise buldings.

I have not dug to the bottom of this one as too many laws/parties are involved. However, following the basics of legislation and regulation involved, the water supplier has an obligation to supply sufficient flow and pressure to the building, and the freeholder has an obligation to make sure the services are available to the leaseholders.
Can I guarantee there is no loophole? About as much chance as anyone else guaranteeing that the supplier/freeholder does not have an obligation.
Nevertheless, when we are talking about a mains pressure of 0.3 bar, we have left the realms of what is good and better; it has become a situation of: any water is better than none.

I think unvented storage cylinders are a fad that are over-promoted by the manufacturer's advertising. They have their uses. I do have an unvented ticket.

No argument there.
Don't have unvented papers myself; apart form tyre kickers, I have no demand for it. My mate can do them, but he never gets asked for them either.

 

[bengasman]

I would not need to offer a solution for a problem, as I would not have allowed the cowboy installation in the first place

You are asked to install a hot and cold water system in a property.
It's a new build with 4 showers , two bathrooms , utility room and kitchen. Their is ample head height.
With no hope of upgrading the mains supply.

That is just nonsense, like I mentioned twice already, it is ILLEGAL, to build a house that does not meet the regs. I specifically asked for an example that EXISTS and IS LEGAL.
Not only that, there is simply no logical reason why an incoming pipe can not be enlarged. You are just trying to dream up a scenario where you can justify your beloved open vent stuff and it is about as credible as a 007 film.
REAL LIFE SITUATION PLEASE. Yours is non-existing apart maybe from the capital of cloud cuckoo land.

The flowrate is 14/lmin.

That is just nonsense, like I mentioned twice already, it is ILLEGAL, to build a house that does not meet the regs. I specifically asked for an example that EXISTS and IS LEGAL.

What system do you propose?
Or do you walk away?

Again, I would propose to bring the incoming mains to a compliant level.
Again, in your scenario, the incoming mains would have been my design and installation, and therefore way over 14l/min.

I do NOT engage in botch repairs; if there is a problem, I either bring the failing parts up to spec, or they can find somebody else who is willing to come up with some spittle and bailing wire solution because the client is too tightfisted to do it properly.

One more time:
Existing/real example.
In England
Legal

 

[Norcon]

You are asked to install a hot and cold water system in a property.
It's a new build with 4 showers , two bathrooms , utility room and kitchen. There is ample head height.
With no hope of upgrading the mains supply.
The flowrate is 14/lmin.

What system do you propose?
Or do you walk away?

A mains system with the same size pipes will provide more litres per minute

Rubbish.
Have you ever installed a h&c water system in a large property?
And can you point to the legislation in the building regulations that state 14l/min supply to a large property is illegal?

 

[David937]

I know that it is an unvented cylinder because:

1. It has the safety valves and all the explosion warnings on it.
2. There is an expansion vessel for it.
3. An unvented cylinder was considered the best option because he has a jacuzzi and two showers.
4. It is written on the cylinder.

I found out about this cold water tank when they were getting there loft converted into a room; they did not remove it and a cupboard was built to house it in.

 

[BingoBongo]

run a cold water tap in the bathroom and see if the water tank refills

what size is it its not a header tank is it?

size of a big shoe box

is there even water in it

 

[Onetap]

The main advantage of a storage tank system nowadays is that they have a type A air gap and are far more resistant to backflow contamination of the mains water supply.

Not needed if the plumbing is installed to spec in which case no contamination will take place..

The challenge was to tell you of a realistic advantage that an open vented system has over a mains-fed system. If I may quote you;

I posted a reward recently for the first who can give me a reasonable/realistic advantage that open vent rubbish offers over mains/sealed.

The reward was drink as much as you want/can for the evening/night.

The offer still stands.

I have done that. An advantage is that an open vented system is less susceptible to back-siphonage. A type AF air gap is suitable for protection with fluid category 4. The usual domestic back-flow prevention devices are only suitable for use with fluid categories 3 (verifiable double check valve). I trust that you have a copy of the Water Regulations Guide?

There you have it, a real advantage. Other real advantages are that open vented systems are cheaper, have fewer mechanical safety devices and have less maintenance requirements.

Mine's a pint.

I anticipate you'll trying to squirm out of it. It seems your high opinion of your own expertise doesn't measure up to your expectations.

A vented system is by definition open to bacteria, water may be crystal clear, it could be lethal, just the same as "clean" air could be toxic as hell.

Yes. But so is the mains supply, as I have detailed above. The overflow and air vent are screned and filtered and the only route for contamination is through some airborne pathogen. I don't know of that having happened. Maybe you know better.

Many mains-fed systems (combis and unvented storage) are incapable of supplying an adequate flow rate to a bath.

Because the pipes are undersized.

No, the mains supply is inadequate to cope with the instantaneous demand. For example, many hotels where all the guests are taking showers at about the same time. The only solution is storage, usually with pressure booster pumps.