The state-of-the-art design of the GB142, with integrated controls, is a rare combination of outstanding quality paired with exceptional value. Utilizing advanced condensing technology, the Buderus GB142 Wall-Mounted Boiler maximizes the heating value of every cubic foot of natural gas or liquid propane. All GB142 Boilers now come with the AM10 outdoor reset control and DHW sensor for control of an indirect DHW tank. The GB142 is approved for 3" solid core PVC horizontal and vertical venting. The small size and minimal clearance requirements of the GB142 Boiler provide tremendous installation flexibility. Thanks to the prefabricated low-loss header, the GB142 Boiler has the fastest installation in the industry. Specially designed with an appropriately sized circulator, this manifold ensures proper flow-rate through the unit. This feature greatly extends the service life of the GB142. By simplifying the piping, the GB142 manifold allows for quicker, easier, and trouble-free installation