measuring water pressure in gravity fed system

[shrike]

Hi gentlemen..

I have a 3 storey town house, cold water tank in loft, ensuite shower on 1st floor, height of 2nd floor is about 2.3m, total head about 3m.

Am looking for a new bar type mixer as replacement, have seen various specs of valves and will go for one suitable for gravity fed system, pressure 0.1-5.0 bar, although some say recommended pressure is 0.5 bar.

Is there a way I can work out how much pressure is coming from the supply pipes to the existing shower. Do I need to check the size of the cold water tank?

I have tried plugging the basintaps in the ensuite with my fingers and turning on as suggested elsewhere in this forum, a bit of water squirts out though.. maybe i need bigger fingers??

Is there an estimated pressure based on the info above?

The existing shower doesnt seem to have any problems.

Also what about the flow rate, do I need to measure this as well?

thank you

 

[Softus]

Is there a way I can work out how much pressure is coming from the supply pipes to the existing shower.

Measure the difference in altitude between the base of the cistern and the shower head position (the spraying part).

Do I need to check the size of the cold water tank?

It doesn't affect the pressure, but the capacity needs to be such that you don't run out of water while showering: 50 litres is plenty; 25 litres will do if your incoming mains flow is fast enough; any less is risking it.

I have tried plugging the basintaps in the ensuite with my fingers and turning on as suggested elsewhere in this forum, a bit of water squirts out though.. maybe i need bigger fingers??

What was the purpose of you doing this?

Is there an estimated pressure based on the info above?

Yes - about 0.25 bar.

Also what about the flow rate, do I need to measure this as well?

Not really - if the pipework isn't contorted then reasonable pressure will result in reasonable flow.

 

[shrike]

thanks for your info softus,

What was the purpose of you doing this?

I think that was to tell if you have mains or low pressure cold water and how balanced the hot and cold are.... but i guess theres no point if I know I have a cold storage tank and hot water cylinder already