The /mm standard horizontal flue kit includes the ° elbow and suitable for condensing boilers only. Getting an energy-efficient boiler is a great start to saving on heating, but what's the purpose of heating your home if the heat is escaping? Cracked or leaking bedford drains and pipes. All you need to know to keep your boiler working in tip-top condition. Rebate amounts are determined by the size and efficiency of the boiler. Have a problem with your septic tank or cesspit? Find your local.