Adding a gas boiler to my baroque heating system (thermal store, woodburner, plate hex for dhw) and looking at control options.
The system is plumbed so that the woodburner always heats the thermal store. There are manual valves to allow the gas boiler to heat the store only (rads then run from the store) or to drive the radiators direct, leaving the store only supplying high pressure dhw.
Question is on control. If the gas boiler is running the heating direct, Opentherm looks like the way to go- if the heating is running from the store then that doesn't really work.
The gas boiler (Intergas Rapid 32) has Opentherm, then a 24v loop and highest priority input is a 240v input.
Questions- will it sulk if I use relays to break the Opentherm circuit when running heat from the store. And will the controller likewise sulk if I break the Opentherm circuit- what I would need it do do is if Opentherm goes away revert to making H1 or H2 outputs live on a call for heat (which are connected to the pump & valve from the store not the boiler).
I think this post would be easier to understand with a schematic, I'll upload a pretty one later today (my working drawing is far too scruffy)
EDIT Should have mentioned, controller is Drayton Wiser 3 channel, rads have all got WiFi TRVs so the original zoning motorised valves have gone.
The system is plumbed so that the woodburner always heats the thermal store. There are manual valves to allow the gas boiler to heat the store only (rads then run from the store) or to drive the radiators direct, leaving the store only supplying high pressure dhw.
Question is on control. If the gas boiler is running the heating direct, Opentherm looks like the way to go- if the heating is running from the store then that doesn't really work.
The gas boiler (Intergas Rapid 32) has Opentherm, then a 24v loop and highest priority input is a 240v input.
Questions- will it sulk if I use relays to break the Opentherm circuit when running heat from the store. And will the controller likewise sulk if I break the Opentherm circuit- what I would need it do do is if Opentherm goes away revert to making H1 or H2 outputs live on a call for heat (which are connected to the pump & valve from the store not the boiler).
I think this post would be easier to understand with a schematic, I'll upload a pretty one later today (my working drawing is far too scruffy)
EDIT Should have mentioned, controller is Drayton Wiser 3 channel, rads have all got WiFi TRVs so the original zoning motorised valves have gone.
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