Safeguard for furnace draft system

Safeguard for furnace draft system

Safety circuit for furnace

Sawdust and wood chip burner

Seal retaining configuration for humidifier

Seal retaining configuration for humidifier

Secondary heat exchanger for condensing furnace

Sectional high efficiency heat exchanger

Self-cleaning air filter system

Serpentined tubular heat exchanger apparatus for a fuel-fired fo

Solar and heat pump powered electric forced hot air hydronic...

Solar and heat pump powered electric forced hot air hydronic...

Solar energy storage and distributing device

Solid fuel warm air furnace

Space heater

Space heater

Space heater with novel fuel line assembly

Space heating and ventilation systems for buildings

Standing pilot furnace with vented vestibule

Standing pilot furnace with vented vestibule