Gas Furnace and AC Systems

A matched home comfort system delivers heated or cooled air when needed. When sized and installed together, you avoid having to retrofit the system to make it work because all the components get installed at the same time. The gas furnace uses gas to heat the air, but a fan to distribute the heated air throughout the house. When switched over to the air conditioner, the same vents deliver the cool air.

Advantages of a Matched System

The air conditioning unit in a matched system goes outside.

With a matched system, you obtain precise temperature control of your home's environment through one device -- the programmable thermostat. Some thermostats have an automatic setting that lets the system decide whether to heat or cool the air based on its settings. Look for these two ratings, the Seasonal Energy Efficiency Ratio and the Annual Fuel Utilization Efficiency. The SEER rating measures the efficiency of the air conditioning unit, while the AFUE tells you the amount of fuel used by the gas furnace -- the higher its rating on either, the more energy efficiency.

Disadvantages of Matched System

The down side to a matched system begins and ends with the increased cost to have it installed. When you have a split system installed, it initially costs more for the two main units, the furnace and the air conditioning. But the savings of a matched system typically appear on the back side -- during usage. You can significantly reduce your heating and cooling costs when you install a matched gas furnace and air conditioning system in your home.

Shared Components

Because the units are installed at the same time, the ductwork accommodates both systems. Vent placement and the size of the ductwork are critical aspects of heating, ventilation and air conditioning systems. By installing both units at once, you save on overall costs as opposed to installing an air conditioning system later. The fan, filter system and ductwork work with both systems, reducing the need for two methods of delivery, which is not as energy efficient.

Energy Efficiency

Matched systems offer greater energy efficiency than systems installed separately, especially when you purchase Energy-Star labeled components. An HVAC professional completes the load calculations to size the individual components of the system to your home's square footage, layout and environmental needs. Systems installed together offer greater energy savings, as the system works as one unit. Installation of independent systems usually results in units sized too big or too small for the home, which cost more to operate. When units are improperly sized and installed independently, you may end up with uneven temperatures, maintenance and humidity problems.

System Maintenance

System maintenance becomes a critical aspect to ensuring the longevity of your home's matched system. Regular semiannual visits, one at the end of the summer for the gas furnace, and one at the end of spring for the air conditioning unit keep your system operating at peak efficiency. Regular cleaning of filters, replacing worn belts and oiling mechanical parts are all necessary to keep the system operating like new.

About the Author

As a native Californian, artist, journalist and published author, Laurie Brenner began writing professionally in 1975. She has written for newspapers, magazines, online publications and sites. Brenner graduated from San Diego's Coleman College.