Chapter 24 Energy Conservation
397
Like hot water heaters, air conditioning
units and furnaces are rated for effi ciency.
The Seasonal Energy Effi ciency Ratio (SEER)
provides a rating for air conditioning equip-
ment, Figure 24-5. This rating is normally
between 10 and 16 for most systems, with
higher ratings signifying higher effi ciency.
Again, energy effi cient systems may cost more,
but they cost less to operate. When making
a decision, compare the extra purchase cost
with the annual savings on energy bills.
A geothermal system is an alternative to
the traditional heating and cooling system.
This system uses a series of holes between
100′ and 400′ deep near the house. Coils,
called a ground loop, are buried in the holes.
This allows the coils to access and use the
temperature found deep below the earth’s
surface, which unlike the air temperature,
is nearly constant throughout the year. See
Figure 24-6. The fl uid in the coils usually
contains a mixture of antifreeze and water.
Inside the house, the pipes from the coils
connect to a heat exchanger.
Figure 24-5. This unit uses the SEER rating
scale. As you can see, it is a less-effi cient model.
Figure 24-6. A geothermal system relies on the constant temperature found deep below the
earth’s surface. In this fi gure, red represents hot fl uids and blue represents cool fl uids.
Fluid
in
Summer
Fluid
in
Winter
Fluid out Fluid out
Pump Pump