Air Conditioner Repair Checklist
1. AC Won’t Turn On
There can be several causes why your central AC system won’t work: an overloaded circuit breaker, incorrect thermostat settings, a turned off switch or an overflowing condensate drain pan.

Tripped Circuit Breaker
Your AC won’t run when you have an overloaded breaker.
To find out if one has blown, go to your house’s main electrical panel. You can locate this metallic device on the wall in the basement, garage or closet.
- Make sure your hands and feet are free of moisture before you touch the panel or breakers.
- Look for the breaker labeled “AC” and confirm it’s in the “on” location. If it’s tripped, the breaker will be in the "off" position.
- Steadily shift the lever back to the “on” spot. If it instantaneously triggers again, don’t touch it and reach us at 814-308-0416. A breaker that keeps turning off could mean your home has an electrical issue.
Wrong Thermostat Settings
If your thermostat isn’t signaling your AC to work, it won’t switch on.
The most important step is ensuring it’s set to “cool” and not “heat.” Otherwise your air conditioner might not start running. You may also have warm air moving from vents since the furnace is on instead.
If you rely on a regular thermostat:
- Replace the batteries if the readout is clear. If the readout is displaying scrambled numbers, buy a new thermostat.
- Ensure the right mode is on the display. If you can’t update it, reverse it by dropping the temperature and pushing the “hold” button. This will cause your AC to run if programming is incorrect.
- Try setting the thermostat 5 degrees colder than the space’s temperature. Your AC won’t start if the thermostat matches the space’s temperature.
Once your thermostat is adjusted properly, you should begin getting cool air quickly.
If you’re using a smart thermostat, like one made by Nest, Ecobee, Lux, Honeywell or Bosch, go to the manufacturer’s website for assistance. If you still can’t get it to work, call us at 814-308-0416 for support.
Turn-Off Switch
Your cooling equipment typically has a shut-down device around its condenser. This switch is commonly in a metal box attached to your house. If your equipment has recently been serviced, the device may have inadvertently been turned off.
Overflowing Condensate Drain Pan 
Condensate drain pans keep the extra liquid your equipment pulls from the air. This pan can be found either under or within your furnace or air handler.
When there’s an obstruction or backed up drain, water can accumulate and initiate a safety feature to turn off your system.
If your pan involves a PVC pipe or drain, you can clear the extra liquid with a formulated pan-cleaning tablet. You can buy these tabs at a home improvement or hardware shop.
If your pan involves a pump, find the float switch. If the lever is “up” and there’s water in the pan, you could need to get a new pump. Call us at 814-308-0416 for assistance.
2. AC Blows Warm Air
If your AC is on but not delivering cold air, its airflow might be obstructed. Or it could not have adequate refrigerant.

Clogged Airflow
Your equipment’s airflow can be reduced by a blocked air filter or dirty condenser.
How to Change Your Air Filter
A filthy filter can lead to a lot of troubles, including:
- Reduced cooling
- Frozen refrigerant lines or evaporator coil
- Intermittent cooling
- Increased cooling costs
- Making your system stop working more quickly
We suggest replacing flat filters once a month, and pleated filters every three months.
If you can’t recall when you last replaced your filter, shut off your equipment fully and take out the filter. You can find the filter in your furnace or air pump’s blower compartment. It might also be located in an adjoining filter case or wall-mounted return air grille.
Hold the filter up to the sunshine. If you see a lot of dust, you should get a new one.
4 Tips on Cleaning Your Air Conditioning System
Greenery, plants and leaves can obstruct your condensing unit. This may reduce its airflow, impact its energy efficiency and impact your comfort. Here’s a way you can get your system operating properly again.
- Switch off electricity completely at the breaker or outside switch.
- Remove greenery debris around the unit. Once you’ve removed bigger refuse within a two-foot space, you can use a fine-bristled brush or vacuum to gingerly remove dust from the equipment’s fins. Warped fins can also hurt efficiency.
- Use a hose nozzle to carefully remove gunk off the fins from inside the system. Don’t get liquid on the fan motor.
- Turn on the power.
Low Refrigerant Levels
When AC units don’t have enough refrigerant, they’ll struggle to remove heat and humidity from the air.
Here are a couple of signs that your equipment is leaking refrigerant:
- It takes too long to refresh your house and you’re continually turning down the thermostat.
- Cooling coming through the vents isn’t as cold as it should be.
- You’re experiencing fizzing or burbling noises when the air conditioning runs.
- Your evaporator coil is frozen due to having trouble handling heat.
Suspect your unit is leaking refrigerant? You need a licensed heating and cooling service professional to fix the leak and restore the correct amount of refrigerant in your equipment. Call us at 814-308-0416 for help.
3. AC Not Blowing Enough Air
When it seems like you’re not receiving ample amounts of cold air, there’s possibly a blockage or disconnection somewhere in your cooling equipment.
- The beginning step is examining your air filter. Replace it if it’s dusty.
- Make sure the registers are open around your rooms.
- If you’re still not experiencing adequate chilled air, you should have your ductwork inspected by a pro like Patterson & Stirling Inc. Your ducts might need to be fixed or reconnected in limited space spots like your attic, basement or crawl space.