poor water flow in whole house

[dj745]

Hi, moved into my house 6 months ago-had to do a lot of renovating and replaced all taps with monoblock type HP taps.

Set up I've got is:

1) Vokera Mynute 28kw system boiler running around 14 rads
2) shower pump running two ensuite showers -pressure/flos is fine here
3) the cold water flow is better than hot water -about 9litres/min
4) had a new water mains line put in -hasn't made much of a difference to cold water flow

Problems I've got are:

1) boiler needs to be more powerful -looking at a worcester 40cdi -converted to run as a system boiler
2) thinking of a megaflow cylinder -which I think will give me better hot water flow -to match that of the cold flow
3) been told that my pump will nto work to power the two showers

I am a bit concerned that I will lose power in the fairly large shower I am currently running with the pump.

Any advice?

 

[adlplumbing]

pump may not be nessary with unvented cyclinder as this gives main pressure so could be adquate in it self

 

[Agile]

You write well but the technical details are totally wrong!

How do you imagine you need a 40 kW boiler for heating a 14 radiator system? Or are they massive rads and you live in a 10 bedroom house and pay £4000 for your gas bills?

With only 9 li/min open pipe mains water flow an unvented cylinder will not work.

They need 22 li/min @ 1.5 Bar dynamic pressure to work well.

Tony Glazier

 

[dj745]

Hi Agile, based on what some local CH/plumbing companies have said (after measuring the estimated heat output of the rads in btu's I think they have said that a 30 kW boiler will 'just' be ok but will need to be replaced if we were to extend the house in the future(which is planned) hence the reason for looking at the 40kW worcester boiler.

My local water board measured the water flow at the mains stop tap on the pavement and gave a measurement of 20li/min which they say is above the minimum levels/requirements