On Mon, 01 Oct 2007 23:19:49 +0100, Andy Hall wrote:

On 2007-10-01 19:18:37 +0100, Olly said:

Well just tested flow rate and its 20 litres a min. Would this be
sufficient for a mains presured hot water cylinder such as megaflo or
would I require the pressure of the water as well.

That isn't how it works. Pressure is not the same as flow.

20lpm would be just about enough for one shower with single, simple
shower head - i.e. not a drencher or ody jets etc.



Does this mean that
in theory a shower would produce about 40 l/min if both hot and cold
are fully open?

No it doesn't. 20lpm is the *total* coming into the house. Some
will go to the shower as cold water, while some will go via the
cylinder, but it can never exceed 20lpm.

The only way that you can make a difference to that is via some means
of storage. This is why roof tanks can deliver large volumes of water.

I declare a plague on both your houses.

It depends on the distribution of the flow resistance a significant
amount is almost certainly the last 0.5m to and through the kitchen
sink tap, especially if flexibles have been used. You might not get
a lot more out of the sink even if the supply to it was in 32, 28, 25 or
22.

So you will get more total flow, certainly not double, and more
than none extra. Anyway 20l/min is quite good for a shower for most people.



--
Ed Sirett - Property maintainer and registered gas fitter.
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