Do 2 single bath taps produce a better flow that mixer taps?

[francspencer]

Hi,

I'm currently rennovating my bathroom in the loft.
The hot tap at the moment takes a good 10mins to fill the bath.
This is currently an old mixer tap.

The pipework is 15mm, with standard iso valves which I am replacing with full bore ones.

As I am also building a structure to hold a the cold water tank and fitting a pumped electric shower. (my mums electrician is doing the wiring)

My question is,

Will the bath fill quicker (from combi boiler) using a mixer tap or 2 single taps? Or is there no difference..

 

[Jordon]

Maybe depends on the incoming pressure and flow rate you have already on the watermain, also how many bathrooms you have and how many taps you have on at once. You can put a house pump in on negative head but need to calculate the tank size and cylinder size to allow for the bathrooms existing. Or jack the cold water storage tank up as high as you can. Oh and not really for the taps as long as they are for combi hp or gravity lp.

 

[Jordon]

Also to add if you are fitting a pumped shower you will have to bin this if you fit a combi unless it's switchable to high pressure eg digital

 

[francspencer]

Maybe depends on the incoming pressure and flow rate you have already on the watermain, also how many bathrooms you have and how many taps you have on at once. You can put a house pump in on negative head but need to calculate the tank size and cylinder size to allow for the bathrooms existing. Or jack the cold water storage tank up as high as you can. Oh and not really for the taps as long as they are for combi hp or gravity lp.

1 bathroom only.
Anybody know the answer to my original question regarding mixer tap?

 

[francspencer]

Also to add if you are fitting a pumped shower you will have to bin this if you fit a combi unless it's switchable to high pressure eg digital

Interesting answer.. may I suggest you re-read my post "pumped electric shower" Its the Mira elite st, which is fed by its own tank, it has nothing to do with the combi as the tank is cold mains fed.

Does a mixer tap restrict flow compared to 2 seperate taps on a bath?

 

[Jordon]

I have read it may you re read my reply. If you change to a combi the house will become mains fed to all taps and showers this means a electric pump in the shower would not be allowed to pump a water main hence it would be redundant unless you are keeping a tank and cylinder with the combi boiler which would just be odd. Also the tap question I answered the taps should make not difference as long as they are for low pressure installations.

 

[francspencer]

I have read it may you re read my reply. If you change to a combi the house will become mains fed to all taps and showers this means a electric pump in the shower would not be allowed to pump a water main hence it would be redundant unless you are keeping a tank and cylinder with the combi boiler which would just be odd. Also the tap question I answered the taps should make not difference as long as they are for low pressure installations.

I already have a combi boiler. The cold water tank is being fitted high up in the bathroom. The tank is fed by the cold water main and then an electric pump is built into the shower unit. Please see the mira elite st on the mira site.
Thanks for the answer regarding the taps.. its so difficult to explain my setup in a few sentences, I suppose I just have to type more.
Thanks again

 

[Jordon]

Ok I'm with you so the main to the house is quite low if you are fitting a pumped electric shower correct? This could be why the flow from the taps is poor! Do you know the flow rate you have from the taps and what Ltr a minute the boiler will allow? Are the basin taps the same flow rate as the bath? You need to teat with a wier cup to find out. Also what is the static pressure at the in coming main?

 

[francspencer]

Ok I'm with you so the main to the house is quite low if you are fitting a pumped electric shower correct? This could be why the flow from the taps is poor! Do you know the flow rate you have from the taps and what Ltr a minute the boiler will allow? Are the basin taps the same flow rate as the bath? You need to teat with a wier cup to find out. Also what is the static pressure at the in coming main?

Yes.
Just measured the flow from the kitchen tap which is located 1.5 meters above the boiler and 5 meters horizontally away.

Hot water = 2 litres in 20 seconds
Cold water = 2 litres in 16 seconds

The bathroom is another 3 meters up above the kitchen.
I purchased 2 x bristan lever taps for the bath in the end as I dont want
to worry about non return valves restricting the flow even more.

I've also added a Calcombi descaler between the new tank in the bathroom and the shower.
Next step is to fit the new carronite bath in the morning, which I suspect will have to be high off the ground for the clicker waste.
I'll hopefully have some more photos after the rugby tommorow.