Gas and oil furnaces provide warm, even heat throughout
your home by circulating heated air through ducts. This section will provide
insight on four main furnace topics:
- How They Work
- Quality
- Comfort
- Energy Efficiency
How They Work
The heat is created by burning gas or oil inside your furnace. Hot gases
that are created pass through curved metal tubing called a heat exchanger
and then out of your home through a metal or plastic vent pipe. At the
same time, the air that circulates through your home passes over the outside
of the heat exchanger and takes on the heat from the hot metal. The warm
air is then circulated through your home.
Quality
Purchasing a brand name that has a reputation for quality and reliability
can save you headaches and extra expense down the road.
New Carrier furnaces, for example, undergo a rigorous series of quality
tests and checks, during production, with many of the tests being performed
on every unit - not just random samples.
We back every furnace in writing, with a 20-year or more limited warranty
on the heat exchanger (the heart of the furnace) and a one-year limited
warranty on the entire unit. Extended warranties are also available.
Comfort
Some mid- and high-efficiency furnaces offer additional features that
provide greater comfort, as well as additional energy savings.
Two-speed furnaces
Two-speed furnaces can run on low speed up to 90% of the time, so they
operate more quietly and run for longer periods of time than single-speed
furnaces. Longer operating periods translate into fewer on/off cycles,
fewer drafts and much smaller temperature swings -- only one or two degrees
instead of the four-degree swings common with single-speed furnaces. Plus,
better air circulation helps prevent air "stratification"
warm air rising to the ceiling and cold air settling on the floor. In
short, you get consistent, even heat throughout your home.
Variable-capacity furnaces
Variable-capacity furnaces provide the ultimate combination of comfort,
efficiency and quiet performance. In addition to the benefits of two-speed
furnaces, they offer "smart" motors than can monitor your homes
comfort needs and automatically adjust the volume and speed of air to
provide the most efficient heating or cooling. They offer added electrical
efficiency as well: the "smart" fan motors on Carriers
variable-capacity furnaces use less electricity than a 100-watt light
bulb. They operate so efficiently that they can actually increase the
efficiency rating of your central air conditioning system and offer you
added energy savings when you use continuous fan operation in any season.
Energy Efficiency
A furnace's efficiency rating, or AFUE (Annual Fuel Utilization
Efficiency), tells you how efficiently the furnace uses fuel (gas or oil).
In general, higher efficiency furnaces mean lower monthly operating costs
for heating.
The government-mandated minimum AFUE rating for furnaces installed in
new homes is 78%. In contrast, many furnaces manufactured before 1992
had AFUE ratings as low as 60%.
Higher efficiency furnaces offering AFUE ratings of 80%, 90%, or up to
96% are also available to help reduce monthly heating costs.
Payback
Usually, the higher the efficiency, the more expensive the inital cost
of the furnace. If you live in a cold climate, you will probably see the
higher cost of a high-efficiency furnace paid back through lower utility
bills in a few short years. Your dealer can use heating data from your
area to help you determine about how long it would take you to recover
the additional cost in energy savings. Of course, after the payback, you
continue to save on your energy bills for the life of the system.