Hi, I am looking for some info on the compatibility between the Evohome system and Thermal Stores.
I have fitted HR92’s to all radiators apart from a towel radiator, I am about to fit the DHW kit (Temp sensor & BDR91) and have a 2nd BDR91 for the Central Heating.

The setup I have is as follows:-
An oil fired System boiler which feeds into a Thermal store(vented with a Feed / Expansion tank) with an external heat exchanger for DHW, the water in the store is circulated to/from the Oil Boiler, radiators and also around a Multi Fuel stove with a back boiler i.e.-
i) Hot water heat exchanger fed from the store with a flow switch i.e. pump only comes on when there is a request for Hot water. Mains pressure water in through the Heat exchanger then out to the taps i.e. No coil inside the store.
ii) All radiators fitted with HR92s bound back to the controller, (apart from a towel rail without a TRV to be used as a heat dump @ 90c). There is a dedicated pump for radiators switched via timer or Over Heat thermostat (90c).
iii) Oil burner currently controlled via timer – separate DHW & CH demand with a dedicated pump.
iv) Multi fuel stove with Back boiler – when it reaches a set temperature a thermostat brings the pump on cycling the hot water between the store and back boiler.

I have 2 BDR91s, I have bench tested them (with 230v lamps as output indicators) bound to the controller and wireless Cylinder stat which works to the configuration below:-
i) Setup the DHW BDR along with the DHW sensor (65c) so that when the temperature falls below a pre-set value the Oil boiler fires and circulates hot water through the store. The only pump that comes on is the Oil burner one, the DHW will be on demand using the flow switch.
ii) Wire the 2nd BDR91 output to the Radiator pump only and NOT the Oil boiler, this will only demand when the temperature in one of the “HR92 monitored” zones falls below the requested temperature. When the radiator pump takes hot water from the store, and the water temp falls below 60c (65c - 5c differential) the DHW BDR will demand the oil burner & Pump to fire to bring the temp back up above 60c (as mentioned in (i)).

I have a wife and 4 kids so there is a high demand for showers in the morning, currently I put a timer on for the heating early and then switch the CH off and fire the Oil burner again for DHW on the theory off warm the rooms up to get them out of bed and then the shower is warm to get the kids to school!
Before I remove the existing timer, is this the most efficient way of fitting the BDR91s?
Thanks in advance!!