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A 19th century businessman in Bozeman, Montana, blacksmith Emil Ketterer, built a large brick residence on the corner lot behind his "General Wagon, Carriage, and Horseshoe Shop". In later years he serviced automobiles, and the shop became known as the "Ketterer Garage". The construction of the Ketterer residence was supervised by his brother in law, a brick mason, in the Vernacular Victorian style. The building was owned and occupied by the Ketterer family until the late 1960's. "The Ketterer" became an art gallery and then offices for a law firm.

The Ketterer building was constructed without fireplaces, and is one of the earliest examples of central heating in Bozeman. The original hot water radiator central heating system is still in place. Radiant Design & Supply replaced the old, inefficient boiler with a Viessmann Vitodens 200. With historic buildings, it is important to preserve the original integrity of the building as much as possible. A photo of the before and after boilers in The Ketterer is below.

Before we replaced it with a new Viessmann Vitodens (96%), the old boiler was setting off CO alarms. The old iron radiation in the building, originally a gravity system, loves the outdoor reset control on the modulating boiler. Even against relatively cheap natural gas, this will pay for itself quickly because the building itself has limited retrofit options available to it.

There is an enormous amount of cost effective energy savings available in this country with these kinds of retrofits.

Viessmann boiler before and after retrofit