I have a Halstead Ace High Boiler. It expels through a horizontal flue. I am building a conservatory. I need to covert the horizonal flue into a vertical flue. I only need it to go up 50 centimetres. BUT..can I get a plumber to do it? Not a chance! One plumber told me that it isn\\\'t possible and I need a new boiler (My current one is only a year old). Any ideas? Help.