Evohome RF Comms Check unexpected result

[Bignomis]

I have recently installed Evohome with wireless cylinder thermostat sensor and BDR91 controlling a two port valve for hot water and another BDR91 to control the two port valve for heating. The system all works well but when I was doing the RF communication check I noticed this was indicating on both BDR91's simultaneously whereas I expected only the hot water BDR91 to show when I did the RF hot water test and similarly the only the heating BDR91 when I did the heat demand test.
Initially I assumed that I had inadvertently bound both BDR91's together so I cleared the binding on both and then reset them individually but there was no change. Anyone any ideas? Thanks.

[Jemster]

That's correct.

Caught me out too when the system was first installed and I asked the question here. I know, it's illogical, it makes no sense, but the RF check will activate both BDR91s.

[Bignomis]

That's correct.

Caught me out too when the system was first installed and I asked the question here. I know, it's illogical, it makes no sense, but the RF check will activate both BDR91s.

Many thanks Jemster. That has set my mind at rest.