Glow Worm 85 / 100 Pilot light

Hi all,
This boiler is at my brothers house and fitted in an outside cupboard - quite old and came with the house when brother bought it a few years ago.
The pilot light goes out after about 20 - 30 minutes each time with DCH on. I am not near it at the moment and there is no manual so have no idea if it fitted with overheat reset or not.
The boiler housing is windproof so I was hoping someone could point me/brother in the right direction - if there is something we can look into.
We are not Gas Safe by the way !! Though quite DIY competent.

There is nothing you can or should do with this old boiler. Very simple controls and a good service should get it up and running again. Call a Gassafe engineer and get it checked out. You won't get any DIY gas advice on this forum.

OK - wilco