Worcester 28i hot water OK, but intermittent c heating fault

[pclimie]

This has happened about once a fortnight over last 2 months now:
If I try and switch on my central heating within a few hours of it previously being on I get nothing, no heat, no attempt to come on. (The trip button has not triggered on top of the boiler)

I get hot water fine - anytime.

If I just leave it to come on next morning it comes on fine.

It's like something is overheating??

Any suggestions or advice gratefully received.

 

[jam1979]

do u get heating if turn it on manualy at the boiler

 

[pclimie]

do u get heating if turn it on manualy at the boiler

No. If I manually turn on the heating it wont come one. This is the problem.

If I leave off, and try after 4 or 5 hours it will work manually eventually! Or leave till the timer brings on in the morning it comes on.