Expensive upgrade of incoming mains-worth it?

[indus]

Hi

I am looking at upgrading my ch/dhw system. My biggest issue at the moment is that I can't run a shower and any other outlet at the same time. I would like to run two decent showers at the same time (and a sink, toilet etc)

As far as I can tell I don't have a pressure issue, ie I have 6bar on the incoming mains.

However my flow rate isn't great at 19l/min @ 3bar. This increases such that it reaches 28l/min@ 6 bar.

The mains pipe under my drive is 22mm.

I've had quotes to have the whole supply upgraded to 32mm.

The private moling company wants circa £1000 to replace the mains under my drive but Thames Water want £2800 to do their end. So my total cost would be £4k.

Of course this is alot of money and I'm trying to figure out whether it would be worth it. If the flow rate would be so dramatically improved that I don't need to think about break tanks, booster pumps etc then it may well make sense.
Booster pumps, break tanks would cost at least as much but then take up space and need maintenance, consume power.

I'd really appreciate any help in trying to accurately figure out how much my flow rate would improve if I spent the £4k and had 32mm pipe all the way from the street main.

Many thanks for looking

 

[indus]

Anybody in a position to shed some light on this matter?

 

[JohnD]

19lpm is quite good. Why isn't it enough for you?

What hot water and cold water system have you got? How many baths and showers and occupants?

What is the size of the pipework inside the house?

 

[indus]

19lpm is quite good. Why isn't it enough for you?

What hot water and cold water system have you got? How many baths and showers and occupants?

What is the size of the pipework inside the house?

Hi John

It isn't enough because I'm assuming a flow of 19l/min is why I can't run two showers (assuming each shower at 15l/min)

I have 5 occupants and after my building work is complete there will be 5 shower rooms. I want to be able to run at least two at the same time without any problems.

At present I have a Thermal Store that I would like to change for an unvented cylinder. Afaik the pipework is 22mm teeing off to 15mm at the outlets.

Thanks

 

[Agile]

Hi


However my flow rate isn't great at 19l/min @ 3bar. This increases such that it reaches 28l/min@ 6 bar.

Many thanks for looking

Can you explain how you get a higher pressure when you take a higher flow rate!

Even considered getting smaller shower heads? A 10 li/min gives a reasonable shower!

Tony

 

[indus]

Hi


However my flow rate isn't great at 19l/min @ 3bar. This increases such that it reaches 28l/min@ 6 bar.

Many thanks for looking

Can you explain how you get a higher pressure when you take a higher flow rate!

Even considered getting smaller shower heads? A 10 li/min gives a reasonable shower!

Tony

Yes I can explain it Tony. The system has a prv in it set to 3bar. As I adjust the prv up to 6 bar the flow rate also increases.

And no I am not considering getting smaller shower heads. If anything I'm thinking of installing one of those 'drenchers' and that uses over 30l/min

 

[JohnD]

you'll be needing a big hot water store, then.

 

[indus]

you'll be needing a big hot water store, then.

Yes I will John. But how much do you think upgrading my whole supply to 32mm will improve my flow? That is the £4000 question

 

[Charnwood]

I'm thinking of installing one of those 'drenchers' and that uses over 30l/min

Whilst the rest of the world is trying its damndest to conserve precious commodities.

 

[indus]

I'm thinking of installing one of those 'drenchers' and that uses over 30l/min

Whilst the rest of the world is trying its damndest to conserve precious commodities.

Yes of course they are

 

[OwainDIYer]

At present I have a Thermal Store that I would like to change for an unvented cylinder.

Why?

A vented thermal store and shower pump(s) is what you should install if your mains pressure and flow is inadequate for a mains pressure unvented.

And no need for annual maintenance inspections with a vented thermal store.

If you're using a drencher shower then shower drain heat recovery is probably worth considering; you will be chucking a lot of hot water down the drain.

 

[indus]

At present I have a Thermal Store that I would like to change for an unvented cylinder.

Why?

A vented thermal store and shower pump(s) is what you should install if your mains pressure and flow is inadequate for a mains pressure unvented.

And no need for annual maintenance inspections with a vented thermal store.

If you're using a drencher shower then shower drain heat recovery is probably worth considering; you will be chucking a lot of hot water down the drain.

Hi

Why do you think I have inadequate pressure? I have over 6 bar on the incoming mains and so can't see what purpose shower pumps would serve.

Thanks for your reply

 

[Charnwood]

Yes of course they are

Well, maybe not the whole world, just we responsible members of it.

I have fine tuned my loo. It now flushes number ones and twos with minimum flush set to about 3 litres. Big bigjobs can be cleared with full flush. You do need a good aim as skidmarks are not always removed with minimum flush.
Our shower head is an aerating type. Once wetted down, shower is turned off until the need to rinse.
I have flow restrictors on the basin taps.
We do not turn on the cold tap until we need to rinse when brushing teeth. There is no need to wet your toothbrush prior to brushing - your mouth is already wet.

No doubt after fitting it you'll be complaining when there's a hosepipe ban and you can't fill your paddling pool.

 

[indus]

Yes of course they are

Well, maybe not the whole world, just we responsible members of it.

I have fine tuned my loo. It now flushes number ones and twos with minimum flush set to about 3 litres. Big bigjobs can be cleared with full flush. You do need a good aim as skidmarks are not always removed with minimum flush.
Our shower head is an aerating type. Once wetted down, shower is turned off until the need to rinse.
I have flow restrictors on the basin taps.
We do not turn on the cold tap until we need to rinse when brushing teeth. There is no need to wet your toothbrush prior to brushing - your mouth is already wet.

No doubt after fitting it you'll be complaining when there's a hosepipe ban and you can't fill your paddling pool.

Congratulations, the survival of our species is now gauranteed as a result of your toilet habits. And I'm sure your friends find your bathing techniques absolutely fascinating.

I however don't and my question is about increasing the water flow to my property. If you have a useful opinion on this then I'd be grateful for it, but with the greatest respect, keep your patronising diatribe to yourself

 

[Charnwood]

Ok, so you want to exchange your thermal store for an unvented cylinder.
How do you expect to get 30lpm+ from it?
How big do you think the cylinder will need to be to service the 30lpm+ showerhead?
What head of water do you have?
Are you thinking of fitting a pump?
Why do you feel the need for a 30lpm+ showerhead?