Gas is currently the most common heating fuel and most new central-heating systems use gas. How efficiently a furnace convert's gas into heating energy is reflected in its annual fuel-utilization-efficiency (AFUE) rating, which is measured as a percentage. The higher the number, the more heat the furnace can bring from each therm of gas. Since,
higher efficient furnaces generate fewer emissions, environmental considerations might also influence your decision.
Furnaces have become more energy-efficient over the years. A gas furnace made in the early 1970s typically has an AFUE of about 65 percent. The lowest efficiency allowed by law for new gas furnaces is 80 percent, and some new models achieve 98 percent--near-total efficiency.
The price of a furnace generally rises in step with its fuel efficiency. A furnace with a 90 percent AFUE might cost $1,000 more than a similar size unit with an 80 percent AFUE. But you can often recoup that additional cost through lower fuel bills over the life of the furnace. How quickly you recover the investment depends on more than just AFUE. The electricity to run furnaces with different AFUEs can vary significantly. The climate where you live, how well your home is insulated, and your local gas and electricity rates also affect payback times.
Furnace filters should be replaced or cleaned at the beginning of the fall season and about once a month during periods of continuous use. To check if the filter needs to be replaced or cleaned, take it out and hold it up to the light. If it looks clogged, replace it with a new filter of the same type. Remember dirty filters reduce efficiency and costly repairs.
Always make an appointment for your furnace's annual checkup. If you have A/C unit it can be inspected at the same time. A well maintained
system in the long run
will save you money and prolong the life of your furnace. Think of it like vehicle maintenance. You wouldn't want to wait till you have 100,000 miles on your vehicle to have your oil changed. Without a yearly cleaning and inspection, a system can wear itself out more quickly, pump deadly carbon monoxide into your home, or just stop working.
Annual inspections should include safety check, filer
replacement, cleaning debris from blower
, checking belts, visual inspection for air duct leaks and an operational furnace test.