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Hi
I'm looking for some help with the design of my evohome system.
My system looks like this:
evohome diagram.jpg
You can see I have 3 motorised valves plumbed in parallel (hot water, underfloor heading and upstairs radiators)
If you ignore the underfloor heating for a moment, the hot water and upstairs radiators are setup as S-plan and this is all working fine with my evohome setup.
Adding in the underfloor heating and the third motorised valve introduces the issue.
Because the "upstairs BDR91" is configured as the heating actuator for the whole system, it comes on and sends water upstairs when my underfloor heating comes on.
I guess Evohome is thinking it has to open the valve for "heating", but this isn't wanted as each valve is plumbed in parallel and I don't actually need that extra valve to come on (the wiring I have turns the boiler on if any of the three valves are opened)
It isn't a huge deal as it's only heating some towel radiators upstairs when it's not needed, but I reckon this must be a common setup and I am sure there is a way to join it all up and make it efficient.
What I think I'm looking for, is a way to only open the upstairs motorised valve when radiator valves (HR92's) request heat. I don't think I can achieve it only with Evohome config, but maybe there is a way to do it with wiring?
Things I tried/though of:
I hope the question makes sense, thanks for any help!
I'm looking for some help with the design of my evohome system.
My system looks like this:
evohome diagram.jpg
You can see I have 3 motorised valves plumbed in parallel (hot water, underfloor heading and upstairs radiators)
If you ignore the underfloor heating for a moment, the hot water and upstairs radiators are setup as S-plan and this is all working fine with my evohome setup.
Adding in the underfloor heating and the third motorised valve introduces the issue.
Because the "upstairs BDR91" is configured as the heating actuator for the whole system, it comes on and sends water upstairs when my underfloor heating comes on.
I guess Evohome is thinking it has to open the valve for "heating", but this isn't wanted as each valve is plumbed in parallel and I don't actually need that extra valve to come on (the wiring I have turns the boiler on if any of the three valves are opened)
It isn't a huge deal as it's only heating some towel radiators upstairs when it's not needed, but I reckon this must be a common setup and I am sure there is a way to join it all up and make it efficient.
What I think I'm looking for, is a way to only open the upstairs motorised valve when radiator valves (HR92's) request heat. I don't think I can achieve it only with Evohome config, but maybe there is a way to do it with wiring?
Things I tried/though of:
- Binding my radiator valves (HR92's) to the "upstairs BDR91" (so that valve is not configured as the "heating" valve) - but they wouldn't bind direct anyway and regardless, I saw there is a limit of 4 and I have more than 4 radiator valves
- Disconnect the wiring between the motorised valves and the boiler and use another BDR91 to control the boiler (although I think this will still open the upstairs valve when the underfloor comes on so isn't worth it)
I hope the question makes sense, thanks for any help!