Electric Shower + Combi Fed Mixer Shower Questions

[BuggBairn]

We're about to start changing out our downstairs bathroom. Our house is a 1960s Bungalow which has an upstairs Dormer added and includes a full sized bathroom. Our downstairs toilet is full sized too due to the original layout.

Upstairs bathroom has a Mixer shower straight from the Combi Boiler. Downstairs has an ancient looking Electric Shower which we don't use. As part of the refit I'm hoping to change the old electric shower out for a new 10.5KW Triton one.

On the plumbing side of things I'd like to do a few pressure and flow tests to be confident that the domestic mains pressure and flow would cope with both showers being in use.

I've borrowed a pressure gauge and threaded fitting to attach to my outside tap. I've done a few initial pressure tests but no flowrate tests.

1. No demand within the house pressure reads 3-3.5 Bar (fluctuates, is that usual?)
2. Upstairs Shower on pressure reads 2-2.5 Bar (again, slight fluctuation)
   
3. Upstairs Shower and Kitchen tap opened fully pressure reads 1-1.5 Bar

I'm under the impression that a typical Triton 10.5KW shower requires at least 1.5Bar pressure and a minimum of 11 litres/min flowrate, does that sound right ?

What additional pressure and flowrate tests would folks suggest I do in order to corfirm I have a decent enough supply to go ahead with my plans ?

Should I carry out these tests when most folks are showering ?. Will there be a big difference on my supply pressure at that time ?.

When I do carryout the tests should I just put demand on the mains like I did for step 3 of my basic pressure tests ?

Quite a few other mods needing done so I'll be hiring a spark to fit the electrical side of things.

Thanks for your time

 

[muggles]

Personally I wouldn't touch Triton with a bargepole, buy a Mira Sport Max instead. Better shower, much better customer service and has a lower minimum operating pressure so it'll work on your supply

 

[BuggBairn]

I'll keep that in mind and read up on that model. Looking more for advice on the best way to run pressure and flow tests please

 

[BuggBairn]

Any further general advice and input on flow/pressure testing my current supply would be appreciated

 

[AGAS]

the search bar at top is a genius

 

[BuggBairn]

the search bar at top is a genius

It couldn't even tell me what 1 + 1 equals but thanks for your input

 

[copea]

At peak times (around 7am and 6pm) over a few days, turn your combi-powered shower on and set it to cold with the shower head removed.

Go downstairs and turn the electric shower on, also set to cold with the shower head removed (to simulate worst-case scenario of highest possible flow at both points).

Measure the flow out of the electric shower with a 10L bucket.
Note how much it fills in 30 seconds and double it.

Work out the average over the few days and see what result you get.

 

[AGAS]

It couldn't even tell me what 1 + 1 equals but thanks for your input

its a genius when you know how to use it its all there


"QUOTE"Any further general advice and input on flow/pressure testing my current supply would be appreciated "QUOTE"BY BuggBairn"

you only have to write flow / pressure testing in search bar its covered everyday

 

[BuggBairn]

At peak times (around 7am and 6pm) over a few days, turn your combi-powered shower on and set it to cold with the shower head removed.

Go downstairs and turn the electric shower on, also set to cold with the shower head removed (to simulate worst-case scenario of highest possible flow at both points).

Measure the flow out of the electric shower with a 10L bucket.
Note how much it fills in 30 seconds and double it.

Work out the average over the few days and see what result you get.

Ive done some preliminary testing and come up with a few queries.

When testing flows from the existing but soon to be ripped out shower I found its supply and outlet hose to be quite restricted.




As you can see the supply tees off from a 15mm feed to what looks like nylon/pvc. Also the outlet hose seems a lot smaller a bore than usual ?

There are two blanked 22mm feeds, one hot and one cold that I intend to reinstate when we fit the over bath shower and bath (there is no bath just now hence the two blanked feeds).

Would this 22mm feed make much difference in terms of delivery over a 15mm supply ? It looks like a 22mm to 15mm reducing T.

What would be the best configuration for piping in a new shower and bath using that 22mm feed ?

I'm intending to have a few other bathroom upgrades that will involve me hiring an electrician, extractor fan, Spot lights and under sink water heater (The boilers pipe run takes and age the supply hot water for washing hands after using the loo).

All cold water pipework is from the mains as we have no tanks upstairs since the house was converted from a bungalow have two floors. I reckon the fact that there is both a 22mm and 15mm supply in the cupboard may have something to do with the original set-up.

Any advice is greatly appreciated