This was before my time, but I presume it had something to do with water collecting in the cellar beneath the Organ, the last entry in the tuning book by Nelson and Co is "I've tried my best" In fact it hasn't even been turned on since 1992.
I started Organ lessons almost a year ago, unfortunatley I have to play on an Allen Digital as the Walker organ is beyond repair. Is it acceptable to approach Churches just for this purpose or would you have to commit to filling in?