Check the thermostat mode and temperature
Easy
Typical time: 2 minutes
Try this safely
- Make sure the thermostat is set to Cool.
- Set the temperature a few degrees below the current room temperature.
- If the screen is blank, check for replaceable batteries if your thermostat uses them.
Stop and request help when
The thermostat is still blank, the system does not respond, or the display shows an error you do not recognize.
Replace or inspect the air filter
Easy
Typical time: 5 minutes
Try this safely
- Turn the system off at the thermostat before removing the filter.
- Check whether the filter is clogged, bent, wet, or installed backward.
- Replace it with the correct size and airflow direction if you have a clean filter available.
Stop and request help when
The filter is wet, the system is frozen, airflow stays weak, or you are unsure where the filter belongs.
Make sure vents and returns are not blocked
Easy
Typical time: 5 minutes
Try this safely
- Walk the main rooms and make sure supply vents are open.
- Move rugs, boxes, curtains, or furniture away from vents and return grilles.
- Listen for airflow after the system has been running for a few minutes.
Stop and request help when
Airflow is still weak, some rooms stay much warmer, or the system runs nonstop without cooling.
Clear leaves and debris around the outdoor unit
Easy
Typical time: 10 minutes
Try this safely
- Keep hands, tools, and hoses away from moving parts and electrical panels.
- Remove loose leaves, grass clippings, or small debris around the outside of the condenser.
- Leave open space around the unit so air can move freely.
Stop and request help when
The fan is not spinning, the unit hums or buzzes, breakers trip, or anything looks damaged.
Check the breaker one time only
Caution
Typical time: 3 minutes
Try this safely
- Look for a clearly tripped HVAC or AC breaker.
- If you know your panel and it is safe, reset it once.
- If it trips again, leave it off and request help.
Stop and request help when
You smell burning, see sparks, hear buzzing, feel heat at the panel, or the breaker trips again.
Look for water near the air handler
Easy
Typical time: 3 minutes
Try this safely
- Look only from the outside of the unit or closet area.
- Note whether water is in the pan, on the floor, near a ceiling, or around a drain line.
- If water is spreading, turn cooling off at the thermostat and protect the area if safe.
Stop and request help when
Water is actively spreading, ceiling stains appear, the thermostat is blank, or the system has shut off.
If the coil or refrigerant line is frozen
Caution
Typical time: Observation only
Try this safely
- Turn cooling off at the thermostat.
- You may run Fan only if your thermostat has that option and the system seems otherwise safe.
- Let ice thaw before expecting normal airflow.
Stop and request help when
Do not chip ice, open panels, add refrigerant, or keep forcing cooling. Request help if freezing returns or the home has no cooling.
After a storm or power flicker
Easy
Typical time: 5 minutes
Try this safely
- Check thermostat settings after power returns.
- Listen for normal startup without standing near moving equipment.
- Write down when the outage or flicker happened and what the system does now.
Stop and request help when
There is a burning smell, repeated breaker trip, loud buzzing, outdoor unit failure, or no cooling in an occupied home.