bathroom basin

[jfk503]

I installed a new mixer tap in my ensuite basin, the connections were 10mm tap tails to 15mm hot & cold connections. I also put in 2 x 15mm service valves, problem is the water flow is now not so good as before.
Can anyone help please

 

[Diyisfun]

You cant get a quart out of a pint pot.

You have reduced the pipe Dia. so you have reduced flow.

 

[jfk503]

Thanks for the reply, I kinda thought that was the problem but just wanted to make sure

 

[stanrog]

Easiest solution - Replace the 10mm tails with flexible tap connection tails , 12mm are available from screwfix.
On reflection this may not work as the screw connection to the tap may not fit, I was assuming they were a universal size but this may not be so.
I replaced my tap tails with flexible hose but took the tails to the plumbers merchants to check i was getting the right screw connection size.

 

[jfk503]

Unfortunately the 10mm tails are screwed in but thanks for advice

 

[MOO1]

You cant get a quart out of a pint pot.

You have reduced the pipe Dia. so you have reduced flow.


Surely you have to take pressure into consideration. I heard of French plumbers pogressively reducing pipe diameter the further the pipe got from the mains, to maintain water-pressure.

 

[TicklyT]

First thing is to have a look at what it says on the box - Are the taps designed for the water pressure range you have available?

Taps designed for use on mains pressure systems will give poor performance on a gravity system, as the waterways through the tap body are smaller.

Mains pressure feeds are at whatever pressure the water company sees fit, but usually 2 Bar or more. Gravity systems usually supply about 0.1 to 0.5 Bar depending on the cold water cistern location.

Increasing the diameter of the tails may improve things a bit, but there's no guarantees...