Hello Peter,
Thanks for your reply. As I said it's being going on since February, I was content that it was mainly water settlement, but Sheila was unsettled by it.
Going to have a look for the bleed valve, when it stops raining.
Being a Lancastrian, you'll know about that. Our town is Waterfoot, , quite right too, usually over the 12 inches.
Regards,
Alan.