Condensing boiler condensate freezing prevention using hydrophobic-coated drain pipe.

摘要

A condensing boiler system 1 has a condensate discharge pipe 3, where at least a part of the inside surface of the condensate discharge pipe is coated with a water repellent (hydrophobic) coating, such as silica nanoparticles. The contact angle of the inside surface of the coated pipe may greater than 120°, and is preferably greater than 150° so as to provide a â superhydrophobicâ coating. The pipe may be made from a polymer selected from a group including polyethylene, polypropylene and polyvinylchloride (PVC). Preferably, the coated pipe is inclined downwards at an angle of 1° to 5° for at least part of its length. In a further aspect, a joint configured to connect with a condensate discharge pipe is disclosed, where at least a part of the inside surface of the joint has a water repellent coating.