Worcester green star 28i junior combi

[blade83]

Hi,

I have been on holiday for 3 weeks.

I have got back today and noticed the heating was on. I've had a look at the Honeywell digital thermostat and it is blank. The Honeywell relay device connected to the boiler had green and red light on. I have switched the boiler to hot water only mode all the way anti clock wise. I think the thermostat battery needs replacing and then rebinding to relay but what I don't understand is why the heating would switch on because of this issue.

I'm not looking forward to my gas bill!!! I need to work ur tomorrow to see when it started. My mum who was looking after the place noticed it today.

Thanks

Nikki

 

[Dan Robinson]

There is a fail-safe parameter that means if the comms fails it brings the heating on to stop grannies freezing to death.

Changing the batteries should not require rebinding.