Gorenje gas oven cutting out

[dazwalsh]

Ive got a Gorenje G162123AW free standing fully gas cooker in one of my rentals that is giving me bother, tenant has been complaining of oven intermittently cutting out. Of course when ive been round rwice to duagnose it its not cyt out in the 30 minutes ive been there. Only just out of warranty too grrr.

Any ideas what part or parts could be the issue? I dont fancy paying through the nose for an engineer to try and diagnose an intermittent fault.