Air Conditioner Repair Checklist
1. AC Won’t Turn On
There can be a few causes why your AC equipment won’t cool: a blown circuit breaker, incorrect thermostat settings, a shut off switch or an overfull condensate drain pan.

Triggered Circuit Breaker
Your air conditioning won’t work when you have a tripped breaker.
To check if one has tripped, locate your residence’s main electrical panel. You can spot this silver device on the wall in the basement, garage or closet.
- Ensure your hands and feet are dry before you check the panel or breakers.
- Locate the breaker labeled “AC” and ensure it’s in the “on” position. If it’s tripped, the switch will be in the "off" position.
- Steadily transfer the lever back to the “on” spot. If it immediately flips again, leave it alone and call us at 301-960-3247. A fuse that keeps flipping could indicate your house has an electrical issue.
Inaccurate Thermostat Settings
If your thermostat isn’t giving a sign to your equipment to run, it won’t switch on.
The first part is checking it’s set to “cool” and not “heat.” Otherwise your air conditioning might not switch on. You might also receive hot air coming from vents being the heat is on instead.
If you have a regular thermostat:
- Put in new batteries if the monitor is clear. If the readout is displaying scrambled numbers, buy a new thermostat.
- Check the correct program is displaying. If you can’t update it, override it by dropping the temperature and hitting the “hold” button. This will force your AC to work if scheduling is wrong.
- Test setting the thermostat 5 degrees colder than the space’s temperature. Your AC won’t start if the thermostat is identical to the room’s temperature.
Once your thermostat is set properly, you should begin getting refreshing air fast.
If you have a smart thermostat, including ones produced 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 301-960-3247 for assistance.
Shut-Off Switch
Your air conditioner usually has a shut-off switch around its outdoor unit. This lever is typically in a metal box mounted on your house. If your air conditioner has recently been serviced, the lever may have inadvertently been turned off.
Blocked Condensate Drain Pan 
Condensate drain pans hold the additional liquid your equipment pulls from the air. This pan is located either beneath or within your furnace or air handler.
When there’s an obstruction or backed up drain, water can become concentrated and prompt a safety feature to switch off your system.
If your pan has a PVC pipe or drain, you can drain the surplus water with a custom pan-cleaning capsule. You can get these tablets at a home improvement or hardware shop.
If your pan includes a pump, look for the float switch. If the switch is “up” and there’s moisture in the pan, you may need to get a new pump. Reach us at 301-960-3247 for support.
2. AC Blows Warm Air
If your AC is working but not providing cold air, its airflow may be obstructed. Or it might not have enough refrigerant.

Blocked Airflow
Your unit’s airflow can be reduced by a plugged air filter or dusty condenser.
How to Change Your Air Filter
A dirty filter can lead to many problems, such as:
- Reduced comfort
- Frosted refrigerant lines or evaporator coil
- Intermittent cooling
- Larger electricity costs
- Causing your system to break down faster
We propose changing flat filters once a month, and pleated filters every three months.
If you can’t recall when you last replaced your filter, switch off your AC totally and pull out the filter. You can locate the filter in your furnace or air pump’s blower compartment. It could also be found in an attached filter box or wall-mounted return air grille.
Angle the filter up to the sunshine. If you see a lot of dust, you certainly should replace it.
How to Clean Your Cooling Unit
Weeds, plants and sticks can block your condensing equipment. This could reduce its airflow, make it less energy efficient and affect your comfort. Here’s a method you can follow to get your unit running well again.
- Shut off electricity completely at the breaker or external lever.
- Get rid of greenery debris around the unit. Once you’ve cleared bigger debris within a two-foot area, you can use a paint brush or vacuum to gingerly remove dirt from the unit’s fins. Warped fins can also impact performance.
- Use a hose nozzle to carefully clean the fins from inside the system. Make sure to avoid getting water on the fan motor.
- Turn the power back on.
Not Enough Refrigerant
When AC units don’t have ample refrigerant, they’ll struggle to remove heat and humidity from your space.
Here are a few flags that your system is seeping refrigerant:
- It takes too long to cool your residence and you’re regularly lowering the thermostat.
- Air conditioning blowing through the ducts isn’t as cold as it should be.
- You’re experiencing fizzing or burbling racket when the air conditioning works.
- Your evaporator coil is frozen on account of having an issue handling heat.
Think your system is leaking refrigerant? You need a certified heating and cooling service expert to repair the leak and replenish the proper measurement of refrigerant in your system. Contact us at 301-960-3247 for assistance.
3. AC Not Blowing Enough Air
When it appears like you’re not receiving adequate amounts of chilled air, there’s potentially a clog or disconnection within your air conditioning system.
- The beginning stage is examining your air filter. Replace it if it’s soiled.
- Make sure the vents are open across your house.
- If you’re still not receiving adequate cold air, you should have your duct system checked by a expert like H&C Heating and Cooling. Your duct system may need to be repaired or rejoined in tricky locations like your attic, basement or crawl space.