John Rumm wrote:
On 22/03/2011 21:15, Old Codger wrote:
On 22/03/2011 10:43, Triffid wrote:
harry wrote:
On Mar 21, 9:12 pm, Old Codger wrote:
On 21/03/2011 19:41, Count de Monet wrote:

Incidentally, I have modern (ceramic disk) mixer taps in the
kitchen. The hot water flows through that tap just a well as it
flows through any of the other traditional taps in the property.

It's not a question of whether the tap has ceramic disks - but
rather whether the tap is designed to operate on low pressure
gravity systems or higher pressure mains-fed systems. There
certainly *are* some modern ceramic disk taps designed to work with
low pressure gravity feeds (and the better on-line retailers make
this clear) - but the majority of modern taps are designed for
mains pressure and provide a poor flow with gravity fed systems.

This (ceramic disk) mixer tap has cold at mains pressure on one side
and hot at low (header tank) pressure on the other. The hot output is
obviously slower than the cold but it is adequate and
indistinguishable from the output from all the other hot taps which
are old fashioned "washer" taps.

Do they make mixer taps with one low pressure side and one high
pressure side?

Not generally. But a tap with large pathways adequate for low pressure
operation will also perform well on high pressure. (unlike the
reverse)

It often surprises me how small the 'hole' is through a typical in-line
isolating valve. You have a 15mm pipe going through to a few inches short of
the tap - and then this isolating valve with a hole not wide enough to poke
a pencil through. Surely this will have a flow restricting effect
(particularly on gravity fed systems)?

--
Triff