New to this excellent forum. I have a strange problem (Honeywell also looking into it). Here goes...

Currently have S-plan unvented system with two 2port zone valves, one controlling CH, the other HW. Each has a BDR91 connected named BDRCH & BDRHW. Also have CS92 thermostat isntalled on unvented HW cylinder. My ATAG IR32 boiler controls a Grundfos Magna pump. The boiler is fired up by either motorised valve trigger switch.

Evohome controller is configured as two 2port valve system with boiler relay set to NONE. The hotwater setup has CS92 bound, BDRHW bound to hotwater valve and BDRCH bound to heatvalve. RF signal all excellent.

HW setup works perfectly, triggers heat when needed and can control temp remotely etc. The trouble is with the CH where I configured 1st zone as radiator valve zone with one HR92 bound as sensor and actuator. When heat demand occurs it does not trigger BDRCH. RF check shows no signal, so I rebind HR92 and RF check only to see it go from excellent to no signal whilst HR92 is syncing. Basically the HR92 looses actuator connection to controller when syncing! I tried other HR92s and even changed BDR91.... same issue.

I experiment and change 1st zone to a zone valve and bind with BDRCH and one HR92 all with success and signal stays up. It works perfectly as a single zone system remotely etc. So whenever I want to create a radiator valve zone using HR92 as sensor and actuator it does not trigger BDRCH.

What am I doing wrong? Its driving me nuts. I hope someone can pint me to what must be an embarrassingly simple fix......

Oh btw I tried the factory resets, reboots, refresh, battery out etc....

Arno