Boiler firing when programmer is set to off

[Jomart]

Please help, I'm losing my mind.

Over the past week my boiler has been coming on even when the programmer is set to off. It doesn't matter if I change it to off or if it's set not to be on because of the timer. Was working as expected up to that point.

I've done a factory reset on the programmer and it's still doing it. Timer is set to 7:30am ON, 8:30am OFF, 6:30pm ON, 10pm OFF. The central heating is on as follows: 7:30am ON, 8:30am OFF, 10am ON, 6PM OFF, 6:30pm ON, 10pm OFF.

The fact its doing it every day at the same time suggests to me it is a setting somewhere but I can't find it.

It's a viessmann boiler with a centaurplus programmer. I'm not sure of age but I think less than ten years.

Do I need a new programmer or a gas engineer?

 

[SJB060685]

2 port zone valves on the system?

 

[Jomart]

2 port zone valves on the system?

If it was failing would it do so at exactly the same time every day? I wondered if there was an internal setting that was overriding the centaurplus programmer, or if the programmer itself thinks it is set to be on when it's actually off.

 

[Jomart]

Just in case anyone else has the same problem, I swapped the programmer and it is working as expected again.