HVAC | Your Key to Indoor Air Quality & Comfortable Living

Despite having been saddled with a rather unglamorous acronym, your home’s “HVAC” system—Heating, Ventilating & Air Conditioning—is the big kahuna when it comes to living chill-free, sweat-free and dust/allergy-free. Indeed, “HVAC” could just as easily stand for “Indoor Air Quality and Comfort” if you’re willing to take liberties with acronym assignment.

After all, your HVAC system, hidden away in the basement, attic or utility closet, is heavily responsible for keeping your home comfortable—snuggy warm during the wintry months, perspiration-free cool in the heat of the summer, and reasonably free of germs, airborne allergens and other irritants year-round.

As such, it deserves periodic attention to keep it purring.

“Regular filter changes are key to efficient and problem-free operation,” says Ted Puzio, principal of Roanoke’s Southern Trust Home Services, which provides HVAC as well as plumbing, electrical, water conditioning and indoor air quality systems and service to surrounding areas, including Smith Mountain Lake. “While homeowners with pets or with lots of dust-raising activity—a houseful of kids, perhaps—may find their filters clog faster, two to three filter changes a year is typical in our area.”

As with your cars and most other mechanical equipment, annual inspection and maintenance by qualified professionals is critical to long and problem-free operation. Says Puzio: “Preventative maintenance helps avoid home heating and cooling emergencies, and periodic ‘tune ups’ generally pay for themselves in energy savings due to more efficient operation. Our ‘Total Care Club’ provides members with a spring and fall visit to clean the system, check pressures and amperage inside and out, and to ensure coolant levels are correct and condensate drains are running free.”

Another possible “trigger” for your annual HVAC maintenance visit might be anticipation of the arrival of a batch of holiday or weekend company. Breakdown of the AC or heating system when you have guests in the house is a major stress and discomfort producer that can tarnish an otherwise delightful visit.

Older systems may also benefit from replacement of the original thermostat with an upgraded programmable model that will automatically adjust HVAC operation (and thus energy usage) based on a family’s living patterns. “You don’t need your system running at full capacity when no one is home or everyone is sleeping,” Puzio notes. “People dash off to work, forgetting to adjust the thermostat, and the system cranks away all day, with no one home. That just burns unnecessary energy and ages the unit prematurely.”

The $100 to $250 investment involved, he says, typically has a relatively short payback period. Puzio’s home uses a more sophisticated wifi-enabled model (up to $500 installed) that allows him to monitor and adjust indoor air temperature from a smartphone. “These can be especially useful for people who leave their homes vacant in winter months, when outside air temperatures (and danger of pipes freezing, etc.) can vary significantly over time,” he points out.

Another recommended HVAC accessory is a humidifier, an add-on unit that will keep indoor humidity at recommended levels of 40 to 60 percent (somewhat lower with really frigid outside air) during heating season. “Really dry indoor air leads to wood shrinkage as well as discomfort and health issues,” says Puzio.

While your HVAC system isn’t the most glamorous feature of your home, it’s among those that have the most influence on comfortable living. Giving it the attention it deserves will help make sure it stands at the ready to deliver problem-free operation. 

Useful “Dirt” Regarding Furnace Filter Selection

Furnace filters are graded on their particle-trapping abilities using the MERV (Minimum Efficiency Rating Value) scale. Most residential filters range from 4 to 14 on the 16-point MERV scale. Manufacturers like to use traditional spun fiberglass filters with low MERV ratings because they filter out the big particles but with very little restriction of airflow, allowing for efficient operation of the unit. Maintaining manufacturer’s specified airflow is also important to getting maximum life from the system’s blower motor and heat exchanger.

An inexpensive MERV 4 filter captures 80 percent of airborne particles 50 microns and larger, but only 25 percent of the particles in the 3 to 10 micron range. An upgrade to a MERV 7 or 8 pleated filter, which will capture 80 to 95 percent of particles 5 microns and larger, provides more aggressive filtration and a reasonable balance between cost and filtration efficiency.

If you’re obsessed with clean air or have family members with allergies or low-immunity issues, high-efficiency (MERV 11 and higher) filters can be considered, but will need to be changed monthly to preclude particle buildup. Such buildup can severely inhibit airflow, overtaxing the blower motor and leading to system freeze-ups. An ultra-high efficiency filter should only be installed on advice of an HVAC technician who may be able to make adjustments that will help the unit operate properly despite increased airflow resistance.

Ted Puzio of Southern Trust Home Services points out yet another option for keeping air clean. “Ultraviolet filtering systems are incredible devices designed to keep the air you breathe at home safe and virus-free. They also combat any mold that may occur from condensation in the summer months,” he says.

In sum, the choice of which filter to buy for your furnace is influenced by how much you want to spend, how pure you want the air, and how diligent you are about changing the filter.