Misinformation about HVAC systems leads to wasted energy, unnecessary repairs, and poor decisions. Let's debunk the most common myths.
Myth 1: Bigger AC Is Better
Truth: Oversized systems short-cycle, fail to dehumidify, and wear out faster. Proper sizing based on load calculations is essential.
Myth 2: Closing Vents Saves Energy
Truth: Closing vents increases duct pressure, which can damage your system and actually increase energy use. Your system is designed for balanced airflow.
Myth 3: Thermostat Location Doesn't Matter
Truth: Thermostats near heat sources (sunny windows, lamps, kitchens) or drafts give false readings, causing your system to run inefficiently.
Myth 4: Ceiling Fans Cool Rooms
Truth: Fans cool people through evaporation, not rooms. Running fans in empty rooms wastes electricity without benefit.
Myth 5: You Only Need Filter Changes Once a Year
Truth: Standard filters should be changed every 1-3 months. Waiting a year clogs the filter, restricts airflow, and strains your system.
Myth 6: Maintenance Isn't Necessary If Nothing's Wrong
Truth: Maintenance prevents problems and maintains efficiency. By the time something seems wrong, you've likely been losing efficiency for months.
Myth 7: Cranking the Thermostat Cools/Heats Faster
Truth: Your system runs at one speed regardless of thermostat setting. Setting it extreme just overshoots your desired temperature.
Myth 8: Keeping the Same Temperature Uses Less Energy Than Setbacks
Truth: Heat transfer is proportional to temperature difference. Lower indoor temperatures in winter (or higher in summer) always reduce energy loss.
Myth 9: Duct Tape Is Good for Ducts
Truth: Despite the name, duct tape fails on ductwork. The adhesive dries out in temperature extremes. Use mastic sealant or metal tape.
Myth 10: Newer Homes Don't Need Duct Sealing
Truth: Even new construction often has significant duct leakage—sometimes 20-30%. Testing and sealing ducts improves any home's efficiency.
Bonus Myths
"My system is fine because it still runs." Running doesn't mean efficient. Systems lose efficiency gradually—you may be paying 20-30% more than necessary.
"Refrigerant needs regular topping off." Refrigerant doesn't evaporate or get used up. If it's low, you have a leak that needs repair.
"All contractors are the same." Installation quality varies dramatically. A perfect system poorly installed performs worse than a basic system installed correctly.
"Higher MERV filters are always better." High-MERV filters can restrict airflow if your system isn't designed for them, causing efficiency problems and damage.
The Cost of Myths
Following HVAC myths typically increases energy costs 10-30% and can lead to premature equipment failure.
When in doubt, consult a professional. Good contractors educate rather than perpetuate myths.