Green Valley Heating Inc Logo 2024 Dealer


Two electrical engineers saw the need for a way to conveniently burn anthracite coal, which was plentiful, but heating with coal had a bad reputation of being dirty and requires maintenance several times a day. Our engineers developed an automatic stoker unit equipped with a coal hopper that held enough fuel for several days. This allowed the coal to be cleanly burned and without frequent maintenance. They then saw the need to make a hot water boiler specifically designed to burn coal and built them in multiple sizes to meet our customers’ needs.

As prices of energy continued to escalate, Keystoker continued its research. Over 60 years of research has developed a patented feed in system, a patented flat grate, and a patented thermal heat exchange, which has produced the highest efficiency possible.

Keystoker – Made in America with American Technology and utilizing American resources is now know internationally for its simplicity, quality, and dependability, all this and still an economical price.


All coal is not the same. Anthracite (hard) is a highly carbonated (82%-86%) form of clean burning coal that is different from the more commonly known bituminous (soft) coal.


• Efficient – Because of its percentage of carbon, it burns at a very high level of BTUs (13,000/lb or 25 million BTUs/ton). Its cost per BTUs is significantly lower than the cost per BTU of electric and oil.

• Clean – Its low sulfur and volatile content makes it extremely clean burning fuel. Anthracite provides virtually no smoke or particulate emmisions.

• Safe – There’s minimal chance of creosote build up which reduces the risk of chimney fire.