Heating - Hot Air Furnaces
A forced-air heating system draws room air through ductwork and a filter into a furnace, where the air is heated. The warmed air is then blown back to rooms through ductwork. With older "gravity" furnaces, the heated air is delivered by natural convection, not by a blower.
A forced-air heating system can be combined with air conditioning for cooling, a humidifier for maintaining proper moisture balance and an air filter. Ductwork is generally metal, wrapped with insulation to help keep heat in. In some cases, flexible insulation-style ductwork is preferred. With a forced-air system, a blower draws cool air in from rooms through ductwork(1). Inside the furnace, the air passes through a filter(2) into a heat exchanger(3) where the burner heats it, then it's blown back to rooms through ducts and registers(4). Excess Flue gases are released out of the house via the vent(5). The thermostat signals furnace to turn on when air temperature dips below a set level. When this happens, a gas valve regulates and delivers fuel to burners and-if there is one-the pilot light. The burner is ignited inside combustion chamber, creating heat that is transferred to the heat exchanger. Combustion fumes are vented out through a flue out the rooftop or, with high-efficiency models, through the wall.
Most furnaces are gas-fired, but other fuels include oil, coal, wood and electricity. With a conventional furnace, natural gas is piped to a burner that's located inside a combustion chamber. There, the gas is mixed with air, then ignited by a pilot light, a spark or a similar device that is controlled by a thermostat. The flame heats up a metal box-the heat exchanger- where room air is heated as it flows through. Exhaust gasses given off by burners vent outside through a flue that goes up through the roof or, with newer high-efficiency models, out through a wall. An electric forced-air furnace uses heating elements rather than burners to heat in the heat exchanger.
To learn more about the brands we carry, click below.
Nordyne
Trane
For frequently asked questions about oil furnaces click here, or for more information contact us.