Cooperative Living May 2015 - 14

ENERGY BANG FOR YOUR BUCK by Tom Tate, Contributing Writer
What's With All These Filters?
W
hen it comes to energy conservation
and home maintenance, it
seems like the choices grow and
grow with each passing year, as evidenced
by light bulb choices (see the article in the
January edition), the plethora of thermostats
and now, air filters. Why so many? It comes
down to providing choice between cost, performance
and longevity.
Filters today range from the inexpensive
fiberglass variety using material that looks
like the handiwork of frenzied spiders to the
high-efficiency particulate arrestance (HEPA)
variety - $30 and up - for the ultimate in residential
air filtration. Also available for your
consideration are washable, electrostatic and
other choices.
The most affordable are the flat filters.
They are usually made of fiberglass and are
the least effective in trapping particles of dirt
and dust. When I pulled the flat filter I was
using from my system, there was barely anything
on it. Pleated filters are next and because
the pleats offer more surface area,
they are far better at trapping airborne debris.
This type replaced my flat filter. When it
was time to change, it had substantially more
dust and debris, obviously a better-performing
product. Having said that, as long as you
are replacing the filter on a monthly basis
and do not have severe allergies, the fiberglass,
flat filters absolutely do the trick.
HEPA filters are the most effective and
are usually marketed as pollen/allergen reducers.
For a person with seasonal allergies,
these may be a good choice. Marketing
names attempt to help buyers pick the proper
filter. A better option is to use the industry rating
system called MERV, minimum efficiency
reporting value, running from 1 to 12 with 12
trapping the most (and smallest) particles.
MERV is intended to allow comparison of
competing filters.
Some filters have an electrostatic charge
to attract more dirt particles, and others are
permanent or washable. Based on personal
experience, they don't seem to be much better,
but as the folks who advertise financial
products like to say, " Your results may vary. "
A word of caution is offered in closing.
Depending upon the type, age and sophistication
of your system, installing a filter with a
high MERV rating may not be the best idea.
Keep in mind here that this higher MERV
rating does not result in a more energyefficient
system. Installing a high-efficiency
filter in your system can cause it to be less
energy efficient.
Why? The filter restricts air flow and increases
static pressure that the blower must
overcome to move air. In other words, your
HVAC system has to work harder. And,
as the high-efficiency filters collect dirt, the
impact on energy use grows. My suggestion
is to take a slow approach and keep an eye
on energy use to see if your system reacts
negatively or positively to the higherefficiency
filter.
Proper filter use is an essential part of
your HVAC system upkeep. Check out the
accompanying CURRENTS piece on maintenance
this month for more on this topic. n
Tom Tate writes on cooperative issues for the
National Rural Electric Cooperative Association,
the Arlington, Va.-based service arm of the
nation's 900-plus consumer-owned, not-for-profit
electric cooperatives.
12
Cooperative Living/May 2015
Cooperative Living May 2015

Table of Contents for the Digital Edition of Cooperative Living May 2015
