Air Conditioner Repair Checklist
1. AC Won’t Turn On
There can be a couple of reasons why your air conditioner won’t run: a blown circuit breaker, wrong thermostat settings, a switched off switch or an overfull condensate drain pan.

Triggered Circuit Breaker
Your AC won’t work when you have a tripped breaker.
To find out if one has tripped, locate your house’s main electrical panel. You can spot this silver device on the wall in the basement, garage or closet.
- Confirm 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” spot. If it’s overloaded, the breaker will be in the "off" position.
- Quickly move the lever back to the “on” location. If it instantaneously trips again, don’t reset it and get in touch with us at 510-343-9841. A breaker that keeps turning off might mean your home has electrical trouble.
Incorrect Thermostat Settings
If your thermostat isn’t signaling your air conditioner to run, it won’t switch on.
The most important point is ensuring it’s switched to “cool” and not “heat.” Otherwise your AC will probably not switch on. You may also have warm air blowing from vents since the furnace is on instead.
If you’re using a traditional thermostat:
- Replace the batteries if the screen is empty. If the readout is showing garbled numbers, replace the thermostat.
- Check the proper mode is displaying. If you can’t alter it, override it by lowering the temperature and pushing the “hold” button. This will force your AC to work if programming is wrong.
- Test setting the thermostat 5 degrees below the house’s temperature. Your AC won’t cool if the thermostat matches the room’s temperature.
Once your thermostat is adjusted correctly, you should receive chilled air fast.
If you have a smart thermostat, including ones manufactured by Nest, Ecobee, Lux, Honeywell or Bosch, check the manufacturer’s website for help. If you’re still having problems, contact us at 510-343-9841 for help.
Shut-Off Switch
Your air conditioner probably has a shut-down switch around its outside unit. This lever is commonly in a metal box mounted on your residence. If your air conditioner has recently been fixed, the lever may have inadvertently been turned off.
Blocked Condensate Drain Pan 
Condensate drain pans hold the additional liquid your system takes out of the air. This pan can be positioned either under or in your furnace or air handler.
When there’s a clog or clogged drain, water can become concentrated and initiate a safety feature to stop your air conditioner.
If your pan involves a PVC pipe or drain, you can drain the surplus water with a custom pan-cleaning tablet. You can purchase these tablets at a home improvement or hardware retailer.
If your pan has a pump, find the float switch. If the lever is “up” and there’s water in the pan, you may need to replace the pump. Call us at 510-343-9841 for assistance.
2. AC Blows Warm Air
If your AC is going but not providing cold air, its airflow might be obstructed. Or it could not have adequate refrigerant.

Blocked Airflow
Your system’s airflow can be reduced by a clogged air filter or dusty condenser.
How to Replace Your Air Filter
A filthy filter can cause a lot of troubles, including:
- Limited cooling
- Frozen refrigerant lines or evaporator coil
- Uneven cooling
- Larger energy bills
- Causing your system to break down faster
We propose installing new flat filters every four weeks, and pleated filters every three months.
If you can’t remember when you last replaced your filter, turn off your AC fully and remove the filter. You can find the filter in your furnace or air pump’s blower compartment. It could also be located in a connected filter holder or wall-mounted return air grille.
Angle the filter up to your light fixture. If you can’t see through it, you certainly should get a new one.
4 Tips on Cleaning Your Air Conditioning Equipment
Brush, plants and shrubbery can get in the way of your condensing equipment. This can restrict its airflow, make it less energy efficient and affect your comfort. Here’s how you can get your unit running smoothly again.
- Shut off the electrical current totally at the breaker or outside device.
- Remove greenery waste around the AC. Once you’ve cleared larger debris within a two-foot radius, you can use a fine-bristled brush or vacuum to slowly remove dirt from the unit’s fins. Warped fins can also hurt performance.
- Use a hose nozzle to gingerly take off dirt on the fins from inside the system. Don’t get moisture on the fan motor.
- Turn on the power.
Insufficient Refrigerant
When cooling equipment doesn’t have ample refrigerant, they’ll struggle to remove heat and humidity from your space.
Here are several symptoms that your equipment is losing refrigerant:
- It takes too long to cool your rooms and you’re regularly lowering the thermostat.
- Cooling moving through the vents isn’t as chilled as it should be.
- You’re hearing fizzing or burbling racket when the air conditioning is on.
- Your evaporator coil is frozen as a result of having trouble handling heat.
Think your system is losing refrigerant? You need a authorized heating and cooling service expert to take care of the leak and refill the proper measurement of refrigerant in your equipment. Reach us at 510-343-9841 for help.
3. AC Not Blowing Enough Air
When it seems like you’re not having adequate amounts of cold air, there’s probably an obstruction or disconnection somewhere in your cooling system.
- The initial stage is examining your air filter. Get a new one if it’s dirty.
- Make sure the registers are open throughout your residence.
- If you’re still not experiencing adequate chilled air, you should have your ducts examined by a professional like Contra Costa Heating & AC. Your duct system might need to be serviced or relinked in limited space locations like your attic, basement or crawl space.