Help with new mains connection

[Plumbing novice]

I am still having trouble with my new plumbing system. My new system will be based on a Megaflo mains pressurised system. My plumber has advised me that as there is 3 ensuite showers/baths and a main bathroom, I need breaker tank and pump aswell. The only way to avoid this is to make sure the new connection to the mains is with a 63mm connection which is the next connection up from 32mm. After some confusion, Scottish Water are now saying they will only provide a 32mm connection. The mains pipe pressure is high at 6-8 bar. Can anyone advise if the high pressure means I can get away with a 32mm pipe. How is flow rate calculated? Should the plumber be able to calculate exactly what size of pipe is required based on load and pressure? If possible, I would like to avoid tanks and pumps.
Thanks in advance.

 

[doitall]

At that pressure 32mm will be fine.

Consideration hasto be given to internal pipe sizes, as well as stored hot water, you may need more then 1 cylinder, so more info.

the next size up from 32mm is 50mm over which you need to chlorinate the supply

 

[fitz1]

i fitted a potterton powermax to a bungalow last jan. think it was 225 ltr storage , with the capability to supply 48 ltr per minute.used 22mm pipe from a 25 mm alcathene to supply boiler ,which supplied kitchen,bathroom with bath , shower , sink, another two bathrooms with sinks , one bath in one and a shower in the other.no problems and customer thinks its brill.

 

[simond]

You can solve all your problems, providing you haven't already bought a new Megaflo, by fitting a DualStream.

DualStream is a packaged pair of an unvented cylinder and accumulator, and is available in GAH and OSO versions, but both are integrated by GAH.

A 500/300 TDDi will solve your issues, no break tanks, no pumps, no 32mm supply. You can run it all off a 15mm supply if you wish. Even better in remote areas, it still pushes out potable water if you have a mains power cut or water outage.

We can't install it for you in Scotland, however if you contact www.gah.co.uk they will refer you to a local specialist who has fitted them before.

We have just completed an install by taking out a 400 litre break tank and 2 Stuart Turner Boostamatic pumps, plus two Megaflos. Customer thinks DualStream is the business. Better flow rate, totally silent etc etc. takes up less room, potable water...

Our customer couldn't understand why the previous plumber had fitted all the other stuff. The only answer is -because they didn't know!

A fringe benefit in not using Megaflo is you don't need to recharge an expansion gap every 12-18 months......

regards

Simon