Water pressure for electric shower

[Sud1]

In my first floor bathroom, I would like to install a Mira 10.8kW electric shower, which requires a minimum maintained water pressure of 1.0bar.

Living on top of a hill, I am concerned that the water pressure may be insufficient: my water pressure gauge reads just over 3.5 bar at the garden tap close to the mains stopcock (the only outlet to which it will fit). The shower head will be some 4.25m higher; will the water pressure decay too much over this height for the shower to work?

Once I tee the supply to the shower off the rising main up in the loft (there is no access any lower in the building), should I avoid 90 degree elbows (but I do not have the kit to bend copper pipe)?

With thanks in anticipation of your advice!

 

[muggles]

Is there a mains fed tap up there? If so, go up and turn it on then go downstairs again and read your pressure gauge while it's running, if it's still showing over 1.0 bar you'll be fine

 

[seco services]

What is dynamic pressure ?

Your static is 3.5 bar so i would say your not going to drop much lower than 2.8 bar if at all.

Your looking for around 1.5 bar on a 10.8kw and min 1.0 bar as you say.
But your not going to have a problem with your pressure with that bar.
and 90 elbows will be fine.

Just fit a full bore isolation valve.

 

[muggles]

Your static is 3.5 bar so i would say your not going to drop much lower than 2.8 bar if at all

Wouldn't rely on that Seco, went to a place not so long ago that had four bar static, but open end incoming main was only giving four litres per minute at next to no pressure...

 

[Dan Robinson]

Just fit a full bore isolation valve.

Wouldn't want to reduce that flow rate now would we?

 

[seco services]

Why did it drop that much ?

 

[muggles]

Incoming main was old iron that was furred right up, they ended up putting a new 25mm MDPE in

 

[seco services]

Incoming main was old iron that was furred right up, they ended up putting a new 25mm MDPE in

 

[muggles]

Hence my suggestion on the tap test rather than just assuming it'll be OK

 

[Sud1]

Many thanks for your kind and swift suggestions; I'll run the upstairs taps and take a further reading, and will make sure that I buy a full-bore isolation valve.

Thanks again! This is the first time I have asked for advice on this forum (having been reading the posts for a while), and I'm really impressed!