Boiler switches off after 10 secs, but ok when cover off??

[dazzawazza]

I have just replaced the fan on my Glowworm Swift Flow 75E.
When I tested it with the covers off the boiler was functioning correctly.
So I put the inner cover back and the outer shell back happy that it was fixed.
However when I turned the boiler on again it runs for 10 seconds then switches itself off, then back on again for 10 seconds etc.
I removed both covers and it was functioning correctly. So I put the inner cover back and the same problem occured.

I suspect there is a problem with air flow. Could the new fan be faulty, it appears to run ok? Or is there an adjustment I have to make on the boiler?

Thanks

 

[WelshMan]

Could be your air pressure switch or possible a blocked venturi.

 

[mrgas]

why did you change the fan ?

 

[dazzawazza]

The old fan was knackered.
It was extremely noisy and would become stuck forcing the boiler to reset.

 

[dazzawazza]

After finding out what an air pressure switch is I checked it and discovered that the red pipe had come off. Must have happened when I put the outer shell back on, the switch is on the side of the boiler and the pipes stick out when the cover is off.

Thanks so much for your advice. I was very stressed before.