Taking advantage of the increased water pressure

[thornaby]

Had indented to modify my pipework to take advantage of the increase in water pressure to use water without the pump running. A leak on my outside water tank kicked me into a action.
A relatively simple modification now allows the incoming mains to push the water around the house without the pump running.
Pump output pressure is around 2.5 bar.
Incoming mains water can vary from nothing up to an incredible 6.5 bar.
Should the incoming pressure drop below the 2.5 bar, the outside tank will feed automatically feed water into the system.
All done without human intervention.
A happy and pump running year to all!

[waddo]

Sounds like a good idea to me, have been thinking of doing it for some time but not gotten around to it yet - too many other little jobs to do and I need to give Catalkoy water supply a longer test - like during next summer - to see if we will EVER get 24/7 water. One question - the majority of my internal pipe work is of the plastic welded variety and I have had that burst (in the pipe itself) when I boosted my supply system to 4 bar - do you think that the normal house pipe system can stand a constant 6.5 bar?

[ElectricianPete]

You need to put a pressure reducing valve in the system to limit pressure to around 3.5 bar.
Also, if you fit a non return valve as well, then no additional valves are required, and if the mains pressure drops or if they turn it off, then you can just turn your pump back on to bring pressure back up.

[waddo]

Ah! So pressure reducing valve just after the water meter will solve the overpressure problem from the mains, then after that in the same system a non return valve so that when they switch off my water I don't end up supplying everyone else in the world from my tank/pump. Should I not fit another non return in the circuit from the pump to the house to stop them trying to fill my tank via my press control and pump? I know the press control "should" stop that happening but maybe, just maybe....... I do love to have a belt and braces attitude along with a bit of string as well - lol.

[thornaby]

The 6,5 bar pressure was the highest I've recorded with a accurate presssure gauge. Although very high I don't think this will be the norm and even at that high pressure would not expect a pipe joint to fail. Fitting a pressure reducing valve (prv) is an option but not one at this stage I would spend money on at this stage. The incoming pressure now is around 3.5 bar, perfect!

[thornaby]

With this modification there will be no need to turn pumps on and off. If the pressure is good the pump won't run and if if it falls below the switching point of the controller (around the 2.5 bar) the tank will automatically supply the house.

[thornaby]

If a p.r.v. is needed , a 3/4" prv can be bought for as little as £23 from toolstation in th u.k., good value if considered against the constant cost of running the pump. The safety valve on the hot water system may need upgrading to around 4 bar, again low cost!

[Groucho]

If there is any chance that your water tank reserve could feed back into the mains supply to other properties your installation is not only probably illegal it's also a downright risk to health and safety.

[thornaby]

Absolutely not, imagine a supply as per the uk, where incoming water was there at a pressure that fed your property. This is what we are trying to achieve but here the incoming water is not always there hence the need for the storage tank.

[cambridge]

I had my installation modified to allow mains water supply direct to the house. Paul did the work at what was a reasonable cost so you could give him a ring 05338425393. No point in giving a price as each system is likely to be different.
No ties or otherwise with Paul.

[Groucho]

Absolutely not, imagine a supply as per the uk, where incoming water was there at a pressure that fed your property. This is what we are trying to achieve but here the incoming water is not always there hence the need for the storage tank.

It's absolutely not OK to install a system where water beyond the meter can theoretically return to the mains from any storage device.... This is illegal in the UK and here. That's why you are not meant to put a hose pipe on mixer taps etc...

If the water in a bulk tank becomes infected with legionella for example the bacteria could be passed onto neighbours if you connect a system with no safeguards to prevent back feeding water to the mains when the mains pressure drops.

[thornaby]

Grouch, having worked on water systems in the NHS for many years I know how strict the water regulations are and quite rightly so. I'am trying understand what you think I have done. There is absolutely no way I can get back flow contamination into the incoming water supply, this is an impossible. So your concerns are needless.

[Groucho]

Grouch, having worked on water systems in the NHS for many years I know how strict the water regulations are and quite rightly so. I'am trying understand what you think I have done. There is absolutely no way I can get back flow contamination into the incoming water supply, this is an impossible. So your concerns are needless.

I never said your installation was a problem but others who know less than you might get a local 'plumber' to create a feed where this could occur..... They need to know what they are doing.

[waddo]

So, I fit a non-return valve after the meter but before the PRV then? You would imagine (anywhere else in the world) that the meter itself would prevent water from flowing in either direction? In particular as the meter I have has a big arrow on it to show which way it must be fitted! If the meter was a type of non-return valve in itself the problem would have been cured at source. I simply want to make sure that the water I have paid for that is in my tank is not sent back out into general circulation so that when the mains pressure comes back again, I do not end up paying for it twice. As an aside, I have one of the old meters and there is NO non-return system on them!

[ElectricianPete]

The way I have done it for myself and others is to link the incoming mains to the outgoing side of the pump with non return valve and prv in the line.
The PRV is about 110 TL here

[thornaby]

The installation at its simplest was for my above ground supply tank as follows.
Fitted a tee piece into the pipe that supplies the ballcock of my tank.
This tee piece is itself teed into the outgoing pipe from the tank.
To prevent what is now mains pressure from entering the tank from the tank outlet a non return valve has been fitted.
I have now fitted a pressure reducing valve, adjusted to around 3.5 bar on the incoming water suppy to the tank.
I have fitted various valves and unions to assist in any maintenance.
So, if the incoming water pressure is when regulated at 3.5 bar this pressure will now supply the pump and pressure controller of the system which is looking for around 2.5 bar.
With the controller being satisfied the pump will never run.
Should the mains water pressure fail, the controller will recognise this and bring the pump in drawing water from the tank.
There will be no need to switch pumps off or operate valves.
In the extremely unlikely event that the mains water never goes off than the tank water that has been stood will need to be used and refreshed by isolating the bypass pipework. This is no different to the additional roof top tank that a lot of systems have.
Without given it much thought I can't see why a below ground water tank should be any different.
A happy and pump free running new year to all!

[ElectricianPete]

Definately fit the pressure reducing valve as a high pressure can knacker the seals on the pump and also cause leaks in any weak flexibles in the house.
It is also a good idea to turn the mains off at the gate if you go away, as otherwise you could come back to a flood if any of your flexible pipes give way.