Dos and Don’ts of Air Conditioners!

Operating an air conditioner efficiently in New York City requires more than just pushing a button on your remote or thermostat. During peak summer heat waves, improper usage habits can quickly lead to sky-high Con Ed electric bills, poor indoor humidity control, and sudden system breakdowns.

To help you get maximum comfort and longevity out of your central AC, window unit, or ductless mini-split, the experts at 212 HVAC compiled this comprehensive list of air conditioning do’s and don’ts.

The DO’s of Air Conditioner Maintenance & Operation

1. DO Replace or Clean Air Filters Regularly

Clean or replace reusable air filters every 30 to 60 days during heavy cooling seasons. Clean filters maintain strong airflow, prevent frost buildup on evaporator coils, and keep indoor dust and allergens under control.

2. DO Use a Programmable or Smart Thermostat

Set up automated schedule profiles on your thermostat. Setting your target temperature 5°F to 8°F higher when you are away at work prevents unnecessary compressor run time while ensuring your home cools back down before you arrive.

3. DO Keep Outdoor Condenser Units Clear

Ensure your outdoor condenser unit or rooftop heat pump has at least 2 feet of clearance on all sides. Remove fallen leaves, trash, or overgrown urban foliage to allow proper heat release from the condenser coil.

4. DO Schedule Annual Professional Tune-Ups

Have a licensed HVAC technician inspect electrical connections, measure refrigerant pressure, clear condensate drain lines, and deep-clean coils every spring before severe summer heat hits.

5. DO Use Ceiling Fans to Supplement Cooling

Running ceiling fans counterclockwise creates a wind-chill effect, making rooms feel up to 4 degrees cooler. This allows you to set your thermostat higher without sacrificing comfort.

The DON’Ts of Air Conditioner Operation

1. DON’T Turn the Thermostat Super Low to Cool Faster

Setting your thermostat to 60°F will not cool your room any faster than setting it to 72°F. Air conditioners deliver cooling at a constant rate; cranking the setting down only forces the system to run longer, wasting energy.

2. DON’T Ignore Strange Noises or Unpleasant Odors

Squealing, grinding, gurgling noises, or musty smells coming from supply vents are early warning signs of electrical failure, refrigerant leaks, or mold growth. Addressing minor issues early prevents expensive emergency repairs later.

3. DON’T Close Supply Vents in Unused Rooms

Closing registers disrupts static air pressure within forced-air duct systems. This increases duct strain, risks coil freezing, and causes duct leakage in unconditioned spaces.

4. DON’T Block Indoor Return Vents or Air Handlers

Avoid blocking wall-mounted ductless heads or floor registers with curtains, tall bookshelves, or furniture. Restricting air intake starves the system of return air and causes premature blower failure.

5. DON’T Neglect Indoor Humidity Levels

Cooling is only half the battle—dehumidification is what makes indoor spaces feel comfortable. If your space feels muggy despite running the AC, avoid setting fan mode to “ON” constantly; use “AUTO” mode so moisture drains off coils between cycles.