Boiler not firing BDR91 Green

[plug_it_in]

I hope someone can point me in the right direction. My setup is CH and HW . CH is triggered by HR80 on every rad. 3 times now the house gets cold and I notice the boiler is off (no power to boiler) . Both BDR91 for HW and CH have green LED so I expect the boiler to be fired up its not. Manually turning off and on BDR91 by the button has no effect. BUT if I power off the central heating system (I have a power switch installed by my hot tank) that drops all power to both BDR91's and I guess the pumps and valves. Then the system fires up as expected. I have no clue what's going on.

[Richard]

Could the problem be external for the evohome system? Normally if the green light is on a BDR91, then the system has been given its demand. Only time this wouldn't be true is if the BDR91's internal relay had failed.

[DHS]

did you ever get to the bottom of this?. I have same problem, 2 x BDR91's with green light but boiler/pump not running until I switch main isolator off/on. Thanks

[Richard]

did you ever get to the bottom of this?. I have same problem, 2 x BDR91's with green light but boiler/pump not running until I switch main isolator off/on. Thanks

Have a heating installer come and look at your system. Most issues are outside of evohome in this instance.

[gedo.kuiper]

I have the same problem. The error code on my CV indicates that the 'anti-oscillationl' program is activated, because the CV controller tries to start the CV more than once within 10 minutes. I wonder if this is induced by the parameter setting on the EVO home controller (Cycle time and minimum time ON). I tried playing with the parameters, but until now now success.