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.