Nest thermostat not controlling heating

[Szuraj]

Last week randomly the heating started playing up, where the thermostat wasn’t firing the boiler up to turn the heating on. However if I do the hot water boost it does. 

also strangely I have a morning hot water schedule set and that would turn the heating on (never did before) 

when I do the heating boost it turns the heating on but not before. 

the link I can use to turn the heating on manually, but strangely now tonight (just over a week later) we now seem to have no hot water, but the heating works when we hit manual or hot water boost.

can anyone shed some light?

[TudorL]

Hi there and thanks for reaching our community. I'm sorry to hear about your issue, but I'll do my best to assist you. Could you please tell me if you have a system boiler with a Y-plan, by any chance? 

[Vladut]

Hi there, just checking in with you. Did you manage to check the last message?

[Szuraj]

A plumber came and the issue was the board behind the thermostat where the arm wasn’t making contact correctly 

[AlexD]

Thanks for keeping us posted here. Did they manage to solve the behaviour and is it working at the moment? 

[Vladut]

Hi there, just checking in with you. Do you still need help?