URGENT No heating but got hot water

[A I Plumbing]

Have a Alpha InTec 30c combi that gives me hot water but boiler cuts out after 30 seconds when calling for heating. It then restarts and tries to go for another 30 seconds and restarts. When I turn on hot water for around 15mins then swap to heating, the boiler then works... Could diverter valve be faulty. Thanks in advance

 

[Deleted member 120897]

Sounds likely to be diverter.

 

[A I Plumbing]

Sounds likely to be diverter.

Cheers. I had suspected it