: > dave wrote:
: >> Thanks for the replies. The basin and suite were put in by myself years
: >> ago, also the feed tank. The taps are a 3 hole job and mix before the
: >> outlet block. I don't want to change these as they match to everything
: >> else in the suite. If as you say Andrew, standard non return valves
: >> give a low flow on tank fed systems ( the head is only about 2.4
: >> do you know of anything I can use??
: > A water pump with a pressure tank and switch? That will raise your tank
: > supply pressure to the mains pressure or more.
: > --
: > Sue
: Thanks but I think at that level of complexity I will just use the water
: shower in. Unless you can balance the pressures to be equal water will
: either cold up hot or hot up cold. I'm a bit surprised there aren't any
: simple non return valves on the market. The problem of getting drinking
: water to a bathroom sink must have been solved in the past, when mixer
: were allowed, without presurising by pump.
Sorry, I'm jumping in at the middle of a conversation, but do I take it the
problem is mains versus tank fed supplies?
If, going by what has been said already, you need to balance mains water to
the same flow rate as a tank, then use a simple manual gate valve, not a
stop cock, on the mains feed. This will reduce the flow of water enough to
balance it to any flow rate of a tank fed system.
When you get the two supplies balanced then one can not dominate the other
so there is no need for any non-return devices. If the mains feed is to
supply potable (drinking) water, then a non-return valve can be installed
before the manual gate valve. This keeps the non-return valve on the high
pressure side of the point where you need to balance your systems and
therefore does not interfere with the flow rate.
I'm probably way off with this, but I've said my piece now. :)