The original combustion condensing vacuum-fired CoRayVac® system with over 40 years of experience. Burners fire in series for the most even heating and highest efficiency in the business. Available in burner sizes of 20M, 40M, 60M, 80M, 90M, 100M, 120M BTU/hr. with system inputs from 20M BTU/hr. to 500M BTU/hr. Single system lengths from 40 feet to 450 feet. Standard Roberts-Gordon three year warranty.
The revolutionary UltraVac controls provide continuous modulation for CoRayVac® burners between 60% and 100% of maximum rated input. Gas and air are changed proportionally to guarantee optimum combustion efficiency. The result is the most efficient gas-fired heating system in the industry, and the most comfortable.