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Applicance
Service Plans
Heating
& Cooling Energy Tips
How BTU's
and EER's work
Maintain
Heating/Cooling Equip
Natural
Gas Safety Tips
Furnace
Efficiency Ratings
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Just like your favorite car, your heating and cooling system
needs a regular trip to the mechanic to keep it purring. Without
regular servicing, heating and cooling systems burn more fuel
and are more likely to break down. With the proper attention,
they can keep you comfortable year-round.
Heat pumps and oil-fired furnaces and boilers need a yearly professional
tune-up. Gas-fired equipment burns cleaner; it should be serviced
every other year. A close inspection will uncover leaks, soot,
rust, rot, corroded electrical contacts and frayed wires. In furnace
(forced-air) and boiler (hot-water) systems, the inspection should
also cover the chimney, ductwork or pipes, dampers or valves,
blower or pump, registers or radiators, the fuel line and the
gas meter or oil tank—as well as every part of the furnace or
boiler itself.
Next, the system should be run through a full heating cycle to
ensure that it has plenty of combustion air and chimney draft.
Contractors can use specialty metersto check for sufficient draft
and also test the air for carbon monoxide.
Finally, it's time for the down and dirty task of cleaning the
burner and heat exchanger to remove soot and other gunk that can
impede smooth operation. For the burner, efficiency hinges on
adjusting the flame to the right size and color, adjusting the
flow of gas or changing the fuel filter in an oil-fired system.
A check of the heat pump should include an inspection of the compressor,
fan, indoor and outdoor coils and refrigerant lines. Indoor and
outdoor coils should be cleaned, and the refrigerant pressure
should be checked. Low pressure indicates a leak; to locate it,
contractors feed tinted refrigerant into the loop and go over
it with an electronic detector.
The Low Blow
Tuning up the distribution side of a forced-air system starts
with the blower. To do the job right, it must first be removed.
The axle should be lubricated, blades cleaned and blower motor
checked to insure the unit isn't being overloaded. The fan belt
should be adjusted so it deflects no more than an inch when pressed.
Every accessible joint in the ductwork should be sealed with mastic
or a UL-approved duct tapes. Any ducts that run outside the heated
space should be insulated. On a hot-water system, the expansion
tank should be drained, the circulating pump cleaned and lubricated
and air bled out of the radiators.
Turn It Up
While thermostats rarely fail outright, they can degrade over
time as mechanical parts stick or lose their calibration. Older
units will send faulty signals if they've been knocked out of
level or have dirty switches. To recalibrate an older unit, use
a wrench to adjust the nut on the back of the mercury switch until
it turns the system on and, using a room thermometer, set it to
the correct temperature. Modern electronic thermostats, sealed
at the factory to keep out dust and grime, rarely need adjusting.
However, whether your thermostat is old or young, the hole where
the thermostat wire comes through the wall needs to be caulked
or a draft could trick it into thinking the room is warmer or
colder than it really is.
Humidifers
A neglected in-duct humidifier can breed mildew and bacteria,
not to mention add too much moisture to a house. A common mistake
with humidifiers is leaving them on after the heating season ends.
Don't forget to pull the plug, shut the water valve and drain
the unit. A unit with a water reservoir should be drained and
cleaned with white vinegar, a mix of one part chlorine bleach
to eight parts water or muriatic acid. Mist-type humidifiers also
require regular cleaning to remove mineral deposits.
Filters
Most houses with forced-air furnaces have a standard furnace filter
made from loosely woven spun-glass fibers designed to keep it
and its ductwork clean. Unfortunately, they don't improve indoor
air quality. That takes a media filter, which sits in between
the main return duct and the blower cabinet. Made of a deeply-pleated,
paper-like material, media filters are at least seven times better
than a standard filter at removing dust and other particles. An
upgrade to a pleated media filter will cleanse the air of everything
from insecticide dust to flu viruses.
Compressed, media filters are usually no wider than six inches,
but the pleated material can cover up to 75 square feet when stretched
out. This increased area of filtration accounts for the filter's
long life, which can exceed two years. The only drawback to a
media filter is its tight weave, which can restrict a furnace's
ability to blow air through the house. To ensure a steady, strong
air-flow through house, choose a filter that matches your blower's
capacity.
Duct cleaning
Inside the walls and floors of 80 percent of American homes run
a maze of heating and air conditioning ducts that connect the
each room to the furnace. As the supply ducts blow air into rooms,
return ducts inhale airborne dust and suck it back into the blower.
Add moisture to this mixture and you've got a breeding ground
for allergy-inducing molds, mites and bacteria. Many filters commonly
used today can't keep dust and debris from streaming into the
air and overtime sizable accumulations can form—think dust bunnies,
but bigger.
To find out if your ducts need cleaning, pull off some supply
and return registers and take a look. If a new furnace is being
installed, you should probably invest in a duct cleaning at the
same time, because chances are the new blower will be more powerful
than the old one and will stir up a lot of dust.
Professional duct cleaners tout such benefits as cleaner indoor
air, longer equipment life and lower energy costs. Clean HVAC
systems can also perform more efficiently, which may decrease
energy costs, and last longer, reducing the need for costly replacement
or repairs. Cleaning has little effect on air quality, primarily
because most indoor dust drifts in from the outdoors. But it does
get rid of the stuff that mold and bacteria grow on, and that
means less of it gets airborne, a boon to allergy sufferers.
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