Energy Adviser: Pets, energy bills might be at odds

Your pet could be raising your energy bill. Pets, especially dogs and cats, become family members. In fact, the American Society for the Prevention of Cruelty to Animals says 37 to 47 percent of households have a dog, and 30 to 37 percent have a cat. Some are home to both. Clark Public Utilities Energy Counselor Amber Hall visits many Clark County homes with pets. So, it’s not unusual for her to hear a bark when she knocks on the door for an energy audit.

“As a dog lover, I know when a dog greets me at a customer’s door there are some pet topics that I probably need to address,” said Hall. “They include filters, closed doors and pet doors.”

Air filters play a necessary role in every heating ventilation and air conditioning system, including catching pet hair and dander along with dirt and pollen. Large particles, like pet hair, block the filter faster so it doesn’t take as long for a filter to clog and need to be replaced. Blocked filters force the unit to work harder and run longer. This extra effort produces higher energy bills and can also lead to HVAC issues requiring repair.

“Pet owners know that their pet’s hair travels everywhere and eventually is sucked into the HVAC system filters,” said Hall. “But they don’t always know what to do about it.”

Keeping filters clean is important for any heating or cooling system. When an HVAC system distributes hot or cool air into a room, it also returns the same amount of air back to the furnace to reuse. All pets shed, some more than others, and their hair finds its way onto filters through that returned air.

Pet hair also gathers in “dust bunnies” and drifts under and behind refrigerators, where it decreases their efficiency. Masses of hair collect on the coils and prevent proper airflow. The clumps of hair act like insulation and prevent cooling coils from doing their job. If not removed often, pet hair can overheat the compressor, shorten the life of the appliance, or raise the cooling temperature so food isn’t kept cold enough.

“With cooling coils hidden behind or below refrigerators, often customers aren’t aware of this problem,” Hall said. She recommends that homeowners read the unit’s manual before cleaning the coils, however. Then unplug the appliance before touching under or cleaning the back of the unit. You might even want to buy a specialized brush for removing the hair, or carefully vacuum it up.

Closing doors may keep dogs and cats off your bed. But, that can backfire if you live in a home with a central heating system. Hall explained homes with closed interior doors put the rooms under pressure by blocking airflow and reduces the ability of the system to share heat. Reducing airflow and heat transfer in a home can increase the utility bill.

When doors are closed and rooms are under pressure, the ventilation system often doesn’t work as intended. Instead, air can be pulled into the home from open areas of the exterior shell of the home and the chimney or furnace flue, which creates a steady draft in the home. The air being pulled inside the home from the outside is unconditioned (not heated or cooled) and doesn’t circulate through the HVAC unit and, so it isn’t being filtered. This unfiltered air contains a lot of particles and pollutants — dirt, dust, humidity, pet hair, and even carbon monoxide.

“It’s better to leave all the interior doors open and use other means, like baby gates, to keep pets out of selected rooms,” Hall said.

Pet doors conveniently let cats and dogs come and go, but improperly installed doors can cause your heating unit to work harder. Because the pet door is a hole in your home, it naturally increases heat loss and raises your energy bill. To help, look for an insulated door with an airtight seal. It might be slightly less intuitive for the animal, but they will learn to use it. A good tip is to remember that if you can feel cool air coming through the flaps, then warm air leaves just as easily.

“Sometimes the best advice I can give, as a dog lover myself, is to turn down the thermostat a few degrees and snuggle up with your pet if you get chilly. They’re natural heaters,” said Hall.

Energy Adviser is written by Clark Public Utilities. Send questions to ecod@clarkpud.com or to Energy Adviser, c/o Clark Public Utilities, P.O. Box 8900, Vancouver, WA 98668.