15mm or 22mm suppy to fixed shower head from diverter valve

[KRW]

Hi Guys

Just in the process of fitting a filler overflow to a new bath and a fixed shower head above it both supplied from a diverter valve.

The Valve has hot and cold feed inlets in 1/2" and two outlets, one in 3/4" which is to be used for the bath, the remaining 1/2" for the shower head.

Question is ...

For the best flow and pressure should i run the pipework from the 1/2" connection on the diverter valve to the shower head in 15mm or 22mm.

The system is gravity fed and the run of pipe from the valve to the shower head will be around a 6m long as valve will be at opposite end of bath to the shower.

cheers for any advice

Keith

 

[tamz]

the run of pipe from the valve to the shower head will be around a 6m long as valve will be at opposite end of bath to the shower.

Some size of bath that one

 

[KRW]

Ho Ho

2m of it is where it goes up the wall which decreases it a little

 

[picasso]

what valves are you using? are you sure they are suitable for gravity systems, your going to be very disappointed unless you have a very tall house with the cold tanks in the attic.

 

[KRW]

what valves are you using? are you sure they are suitable for gravity systems, your going to be very disappointed unless you have a very tall house with the cold tanks in the attic.

sorry but i don't understand, please can you explain why ?

the system is gravity fed ( has a cold water header tank in loft for hot water tank) regards height of house ...normal sized house with two levels and a loft space.

there is already a shower in another room on the same level and that functions perfectly well which was installed when we moved in so i don't know the supply sizes other than its a Mira shower with hot and cold inlets to the exposed valve in the shower itself...

just enquiring as to which would be the best size pipe to run from the diverter valve which will act as a mixer valve and pretty much the same as on monobloc taps and with regards to getting the volume and pressure of water to the shower head.

 

[picasso]

here is an example

http://www.boundarybathrooms.co.uk/...ource=google&utm_medium=sfeed&utm_campaign=bb

this valve needs 2 bar to work properly, you need to read the instructions that came with your valve , they are not all suitable for gravity systems.

 

[KRW]

Hello Picasso

this is the one which i presume is ok as is rated at 0.5 to 5.0 bar

http://www.4bathrooms.co.uk/index.p...ront-gt320-manual-concealed-shower-mixer.html

 

[picasso]

so you need a minimum of 5 metres between the valve and the cold water tank for that valve to function properly, might be an idea to look at pumping your shower or rethinking what kind of valve you need,

 

[KRW]

forgive me for doubting but why 5 metres, what installation has 5 metres from a diverter valve to the tank when they are generally installed in bathrooms which then only have loft space above.

as i mentioned earlier the other showers performs ok so is it something regards the diverter plunger that you are refering to that needs a pressure to operate it and keep it open...confused

 

[Richard C]

your going to be very disappointed unless you have a very tall house with the cold tanks in the attic.

I'd go along with that; but it rather depends on what you consider as OK . Unless you have an almost direct vertical feed with large bore pipes or you site the shower on the ground floor of a 2 story property, gravity fed HW/CW systems are total cack for modern shower/bath systems. The bath may “struggle on” to a degree but you’ll wonder why you ever bothered with the diverter shower &, if youve picked a high pressure unit, it may not work at all!

 

[KRW]

i might have given you guys some bum info here earlier ....

its the the hot water that is supplied from an immersion heater type cylinder which lives in an airing cupboard on the landing and is fed from a tank (gravity fed ?) from in the loft ..

the cold water is from the mains (mains pressure)

when i mentioned gravity fed earlier i thought thats what i had...seems not
or have i got it all wrong and upside down...

 

[Richard C]

OK; but the fact you have mains CW & gravity HW will give you even more problems. The gravity HW feed is going to be your limiting factor as this governs the HW flow rate. The mains CW flow rate will be fine but as it’s going to be far in excess of the HW flow rate & will vary, you’ll find it almost impossible to balance the pressure of the H/C water system feeds. At best the flow rate will be abysmal & it will likely play havoc with any shower/bath thermo valve as it tries to stabilise the water temperature. My advice is to pump it or you very likely to be disappointed, especially with the shower; but, as I said before, it rather depends on what you consider as acceptable.

 

[KRW]

Hi Richard,

thanks for your input, i appreciate the gravity HW feed is a limiting factor with non pumped systems but it works ok with the other shower in the next room which is a mira and which balances the pressure of the H/C water system feeds with a thermostat valve and gives a decent enough performance.

there will be no shower/bath thermostat in this system with the bath and shower both fed from the diverter valve, the on/off handle pretty much setting the temp as you would do with a bath mixer tap.... is that what i would have problems balancing? i figured this set up would be ok as it is along the same lines of a bath mixer with diverter to shower such as those hand held jobbies and the like.

cheers, Keith

 

[picasso]

are you sure your other shower is mains cold / gravity hot ? your diverter valve is unsuitable for your system as it is now, as already said you need to either pump the hot and cold or put in a mains system, your not having much luck are you

 

[KRW]

are you sure your other shower is mains cold / gravity hot ? your diverter valve is unsuitable for your system as it is now, as already said you need to either pump the hot and cold or put in a mains system, your not having much luck are you

hello picasso

never have had much luck with either wood or pipe things

you might have guessed by now that i am not a plumbist....

yes mains cold and hot water from cylinder fed by header tank in loft...so i have a mains system....dont i ?