Thank you for your enquiry. Unfortunately the assurance that my leaking boiler would not cause damage to the downstairs flat proved to be unfounded. My neighbour has been affected, which has caused further acrimony. I have had to employ another plumber who drained the system and checked the damage downstairs. This should have been done by the plumber who came. He assured me that this would not happen, even though the boiler was leaking badly. I paid over £100 for the service. I trusted his judgement which was a mistake. I am hoping that his insurance will cover the costs incurred.