Have had a customer call me this afternoon saying the builder knocked the flue pipe last week and now there is water continuously from the flue. Its a floor standing ideal mexico with an open flue. He says it happens even when not raining. I only completed my ACS in April so am fairly new with boiler and this will be first open flued ive worked on. Anyone got any ideas what could be? as its not condensing boiler. I was thinking maybe blocked flue, will do a spillage test. But didnt know if anyone had any ideas? Looking at an ID situation as flue is leaking so will be capping off by looks of it.