To reset your air conditioner, start by turning it off at the thermostat. Then, shut off power to the AC system at the circuit breaker. Some units have a dedicated "reset" button; if yours does, press and hold it for three to five seconds. If your air conditioner doesn't have a reset button, or if you are resetting it after a power outage, leave the circuit breaker off for at least 30 minutes to allow the system to reset itself. Afterward, turn the power back on at the breaker, turn on the AC from the thermostat, and set it to "cool" to test the system.

The best way to compare HVAC quotes is getting a few detailed quotes from local companies with good reputations. Then, go over the quotes line by line. Protect yourself by insisting on in-person estimates that include equipment manufacturer names, model numbers, SEER ratings, amounts and numbers of materials, details of warranties on equipment and labor, and other specifics. 

Knowing the exact equipment and materials is the only way that you can fairly compare quotes. Quotes that are much lower than others can be a sign that the company isn’t providing the best quality service or materials.

Window AC units use a fair amount of electricity, but significantly less than central AC systems. Because they are more energy-efficient for cooling individual rooms or small spaces, their usage is comparatively low. On average, a window AC unit consumes between 500 and 1,400 watts, while a central AC system uses over 3,500 watts—meaning a window unit uses about one-third of the energy. This typically translates to a monthly running cost of $15 to $40, although this can vary depending on external factors.

Yes, a dirty evaporator coil can freeze up. Dirty evaporator coils can’t absorb or transfer heat properly. The dirt and grime restrict airflow, which is needed to move heat throughout the system properly. Your air conditioning unit could freeze over, or it can cause your heat pump to freeze.