The Defiance Company of Calumet, MI produced a line of "add-on" central heaters with the Volcano brand name - in the period from 1978 to the mid-1980's. - These units were made in hot air and hot water models, both designed to add-on to an existing Central Heating system and allow the burning of wood for Central Heating.
As the company grew, the introduced the Masters Choice line - freestanding and fireplace insert models with the same heavy-duty construction as the central heaters.
The company quietly disappeared (along with many others) as oil become very cheap in the mid-80's and energy awareness faded from the American scene.
(furnace sell sheet)
Boiler - VolcanoIII Manual:
Stove sell sheet front
Insert Sell Sheet
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