I have 5 motorised valves in my house and want the fifth motorised to switch on when all four of the other motorised valves switch off, if one of the four motorised valves is on the fifth motorised valve must remain closed.

Any suggestions appreciated............I'm thinking of smoe sort of relay??

In an earlier contribution to this discussion,
Fatboise wrote:

I have 5 motorised valves in my house and want the fifth motorised to
switch on when all four of the other motorised valves switch off, if
one of the four motorised valves is on the fifth motorised valve must
remain closed.

Any suggestions appreciated............I'm thinking of smoe sort of
relay??

It depends on how you are using the valves at present. Most 2-port valves
have a set of volt-free change-over contacts which switch when the valve is
fully open. The COM and NO contacts of these are used in S-Plan systems
(wired in parallel) to switch the boiler and pump on whenever one or more
valves are open.

If you're *not* already using the volt-free contacts for anything else, you
could use them to control your fifth valve. You would have to use the COM
and NC contacts - wired in *series* - to control the motor of your fifth
valve. Then, if *any* of the 4 valves opened, the contact would be broken
and the 5th valve would close.

It takes a finite time for a valve to open or close, of course, so the
status change won't be instant. Does that matter?
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

I have 5 motorised valves in my house and want the fifth motorised to
switch on when all four of the other motorised valves switch off, if
one of the four motorised valves is on the fifth motorised valve must
remain closed.

Perhaps you are in the market for an automatic bypass valve instead?

Christian.

On Wed, 16 Nov 2005 01:56:33 +0000, Fatboise wrote:


I have 5 motorised valves in my house and want the fifth motorised to
switch on when all four of the other motorised valves switch off, if
one of the four motorised valves is on the fifth motorised valve must
remain closed.

Any suggestions appreciated............I'm thinking of smoe sort of
relay??

I suspect that you might be looking for an automatic bypass?

If you are seriously lucky all the 4 valves might have the white wire as
Set Square mentioned.

If they don't (almost certainly the case) you would need a simple mains
replay unit to generate the opposite of the boiler demand which you can
then feed to the 5th valve.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

In an earlier contribution to this discussion,
Ed Sirett wrote:

On Wed, 16 Nov 2005 01:56:33 +0000, Fatboise wrote:


I have 5 motorised valves in my house and want the fifth motorised to
switch on when all four of the other motorised valves switch off, if
one of the four motorised valves is on the fifth motorised valve must
remain closed.

Any suggestions appreciated............I'm thinking of smoe sort of
relay??

I suspect that you might be looking for an automatic bypass?

If you are seriously lucky all the 4 valves might have the white wire
as Set Square mentioned.


If the 5th valve *is* to provide a by-pass on an S-Plan-Plus system, then
using an automatic by-pass valve instead would indeed be the way to go. In
this situation, the volt-free contacts on the first 4 valves would already
be in use (as I indicated) and would not be available for switching the 5th
valve without additional relays.

He didn't actually say what any of the valves were used for - so I gave a
generic answer - but I suspect that it *is* a central heating system!
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

Fatboise wrote:


I have 5 motorised valves in my house and want the fifth motorised to
switch on when all four of the other motorised valves switch off, if
one of the four motorised valves is on the fifth motorised valve must
remain closed.

Any suggestions appreciated............I'm thinking of smoe sort of
relay??

If you're planning to use this instead of an automatic bypass valve to give
the boiler's output somewhere to go when all the other zones are off it's
perhaps worth noting that there will be a delay of a few seconds between
the last of the normal zone valves turning off and the bypass zone valve
opening. This could perhaps be enough to upset your boiler and scupper the
whole system.