Air Conditioner Repair Checklist
1. AC Won’t Turn On
There can be a couple of explanations why your AC unit won’t cool: a tripped circuit breaker, incorrect thermostat settings, a shut off switch or an overflowing condensate drain pan.

Tripped Circuit Breaker
Your cooling won’t turn on when you have an overloaded breaker.
To find out if one has blown, locate your house’s main electrical panel. You can spot this metallic box on the wall in the basement, garage or closet.
- Ensure your hands and feet are free of moisture before you check the panel or breakers.
- Look for the breaker identified “AC” and make sure it’s in the “on” location. If it’s tripped, the lever will be in the "off" position.
- Steadily move the breaker back to the “on” location. If it immediately trips again, leave it alone and contact us at 805-242-9638. A breaker that keeps tripping might mean your residence has an electrical issue.
Wrong Thermostat Settings
If your thermostat isn’t signaling your equipment to run, it won’t switch on.
The most important part is making sure it’s set to “cool” and not “heat.” Otherwise your air conditioner may not start running. You might also get warm air moving from vents since the furnace is going instead.
If you have a regular thermostat:
- Swap out the batteries if the monitor is blank. If the screen is displaying scrambled letters, replace the thermostat.
- Make sure the proper option is on the display. If you can’t alter it, override it by decreasing the temperature and pushing the “hold” button. This will force your AC to work if programming is not right.
- Test setting the thermostat 5 degrees cooler than the space’s temperature. Your AC won’t work if the thermostat is identical to the space’s temperature.
Once your thermostat is calibrated accurately, you should begin getting cold air promptly.
If you have a smart thermostat, including ones made by Nest, Ecobee, Lux, Honeywell or Bosch, check the manufacturer’s website for assistance. If it still won’t work, contact us at 805-242-9638 for assistance.
Shut-Down Switch
Your cooling equipment probably has a shut-off device near its condenser. This lever is commonly in a metal box mounted on your home. If your unit has recently been maintained, the lever may have inadvertently been turned off.
Overflowing Condensate Drain Pan 
Condensate drain pans hold the additional condensation your system takes out of the air. This pan can be situated either beneath or in your furnace or air handler.
When there’s a clog or backed up drain, water can accumulate and trigger a safety feature to turn off your unit.
If your pan has a PVC pipe or drain, you can get rid of the additional condensation with a special pan-cleaning tablet. You can buy these tabs at a home improvement or hardware retailer.
If your pan involves a pump, look for the float switch. If the mechanism is “up” and there’s water in the pan, you may need to get a new pump. Reach us at 805-242-9638 for assistance.
2. AC Blows Warm Air
If your AC is running but not cooling, its airflow may be congested. Or it may not have sufficient refrigerant.

Obstructed Airflow
Your system’s airflow can be limited by a clogged air filter or dirty condenser.
How to Replace Your Air Filter
A filthy filter can cause many troubles, such as:
- Limited airflow
- Frosted refrigerant lines or evaporator coil
- Uneven cooling
- Larger electricity bills
- Leading your system to break down sooner
We propose replacing flat filters once a month, and pleated filters every three months.
If you can’t recall when you last replaced your filter, turn off your system fully and remove the filter. You can spot the filter in your furnace or air pump’s blower compartment. It might also be found in an attached filter box or wall-mounted return air grille.
Tilt the filter up to the light. If you see a lot of dust, you should buy a new filter.
4 Steps to Cleaning Your Cooling System
Greenery, grass and shrubbery can get in the way of your condensing system. This can limit its airflow, impact its energy efficiency and impact your comfort. Here’s a way you can get your unit operating properly again.
- Switch off power fully at the breaker or outdoor switch.
- Clear vegetation rubbish around the air conditioner. Once you’ve gotten rid of larger clutter within a two-foot range, you can use a paint brush or vacuum to carefully remove dust from the equipment’s fins. Warped fins can also hurt efficiency.
- Use a hose nozzle to slowly clean the fins from inside the system. Be careful to avoid getting moisture on the fan motor.
- Turn on the power.
Not Enough Refrigerant
When air conditioning equipment doesn’t have ample refrigerant, they’ll have to work much harder to remove heat and humidity from the air.
Here are a couple of indications that your equipment is seeping refrigerant:
- It takes too long to refresh your residence and you’re regularly turning down the thermostat.
- Air conditioning coming through the ducts isn’t as cold as it should be.
- You’re hearing fizzing or burbling noises when the AC is on.
- Your evaporator coil is frozen due to having difficulty absorbing humidity.
Think your unit is leaking refrigerant? You need a licensed heating and cooling service professional to fix the leak and replenish the correct measurement of refrigerant in your unit. Contact us at 805-242-9638 for support.
3. AC Not Blowing Enough Air
When it seems like you’re not having enough cold air, there’s possibly a blockage or disconnection within your cooling system.
- The beginning step is looking at your air filter. Buy a new one if it’s filthy.
- Make sure the registers are open across your house.
- If you’re still not receiving adequate chilly air, you should have your ductwork inspected by a professional like Allstar Heating & Air Conditioning. Your duct system might need to be fixed or rejoined in hard-to-reach areas like your attic, basement or crawl space.