Mine has not been as bad as that.
I have been in this house 18 years and I'm sure it was installed many years before then.
It's a Turboflush T11 and itself has never failed on me.
Yes the non return valve did and I replaced that with one JP advised, I think I need to replace that again though (or clean it out).
Apart from that it's still going OK, although it does go off at random intervals, but that imo is because the cistern keeps overflowing at a drip.
The sound level from it is not that bad for the second or two it's going for during this.
Still it is over 20+ years old and French so it does need replacing when I redo the downstairs loo room.
I'm trying to prime the wife that we need something a bit better than the sub £150 models but she's not happy at £400 so I'm still looking.
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