Tripping tumble dryer

cobwebs on the elements?

Yep could be - I'll replace the mains filter (again, as a precaution) and have a good look round inside. The machine is in a dryish cellar - so that won't help with curious insects.

I posted here 3 or 4 years ago about the same problem with our DCU7230. It's been ok for the last few years, but now you've posted it looks like it might reoccur! I still don't understand why the RCD tripped at turn off. I guess there's some sort of short-circuit occurring, but how and why seems very strange.

Is there some component which is switched in at the end of cycle? Perhaps a cooling fan or something? It is possible the insulation is weak on that component causing earth leakage, but it wouldn't cause a trip until it's energised.

Theo

I had an issue with turn-on, which I presumed was due to spike in suppressor current that passed to earth at switch-on.

Removing a connection to earth solved the problem.

Door release?

It was definitely the filter. At the end of the drying cycle I immediately switched the drier off by its push-button mains switch. This is a double-pole switch, and the only component between it and the mains supply is the filter. The fault disappeared when a new filter was fitted, and it is still fault-free almost 4.5 years since replacement.

Perhaps when it cooled down it short-circuited somehow, but it didn't seem that warm to me to be affected by cooling down.

Just FYI, the old replacement filter had burst; lots of sticky fluid. And that was a replacement I got from espares. Althought he photo on their site showed a different (possibly updated) design, they supplied a filter identical to the original.

Anyway, I got the replacement direct from Beko this time, and it looks completely different. The dryer works, but I won't know for sure until I've saved up enough to put it on a full cycle . . .

This is the one I used:

It's been fine for 3 years (not 4.5 as in my reply). The original which failed showed no physical damage at all.

Yes, that was the design pictured with the last replacement - but they sent the original type.

This was the original type fitted to mine: