Why Isn’t My Air Conditioner Blowing Cold Air?

Heat waves in California can arrive seemingly out of nowhere, and few things are as inconvenient as when your AC won’t blow cold air or turn on.

While AC systems are complicated, some repairs are easy if you have the right information. Find simple maintenance and repair tips below for AC breakdowns. If your air conditioner still isn’t blowing cold air but running after troubleshooting, our team of HVAC experts at Service Champions can help.

5 Steps for Basic DIY Troubleshooting

When your central air isn’t blowing cold air, weak air, or no air at all, the solution can be as simple as replacing thermostat batteries or swapping an air filter. Try the following troubleshooting tips to resolve minor problems or identify issues to communicate to your HVAC technician.

1. Check the thermostat

Check your thermostat before anything else, and ensure that it’s on and set to cool. If you have a programmable thermostat, verify that the temperature settings are correct.

If your thermostat doesn’t have power, swap out the batteries for fresh ones. If it’s hard wired, look for wire corrosion or other damage, and check your electrical panel for a tripped breaker, which will be in the center or off position — turn it to the on position to restore power.

2. Replace your air filter

Depending on your home, AC air filters require replacement approximately every three months. Without regular replacement, air filters can accumulate dust, pet dander, and other debris that can eventually slow air flow to the AC unit and prevent proper cooling.

To replace your air filter, identify the correct replacement model in your owner’s manual. Locate your system’s air filters, which are typically behind a return air duct or the air handler cabinet. Remove the front panel, and replace the filter with the arrow on it pointed toward the furnace.

3. Verify power connection

If your AC isn’t running or blowing air at all, it may be disconnected from power. Check that it’s plugged into a power source, and examine it for any wiring damage. Refer to the electrical panel again to check for tripped breakers, and flip them back on as needed.

3. Clean the drainline

Over time, the outside AC unit and its attached drainline and drain pan can accumulate dirt and debris. Since these lines drain excess water from the humidity indoors, build-up can lead to system clogs and back-ups that may shut your system down or prevent it from cooling.

To flush the drainline, follow these steps:

  1. Disconnect power to the AC system.

  2. Find the access point on the drain line, usually a T-shaped fitting with a cap.

  3. Wearing gloves, remove accessible debris by hand.

  4. Pour either hot water or vinegar down the pipe, and allow it to sit for 30 minutes.

  5. Once the clog clears, flush the line again with water.

4. Inspect the condenser unit

The condenser in your outdoor AC unit maintains proper refrigerant pressure. This unit can build up debris, such as leaves, dirt, or vines. During the California fire season, soot can be particularly cloying. All this build up affects the outside condenser’s ability to transfer heat from your home outside. Use a hose or gentle brush to remove accumulated debris.

5. Examine the blower

The blower fan is located in the air handler unit. Turning the power off first, check that the fan isn’t obstructed and that its bolts and components are properly tight. If it has bent blades, you may be able to gently bend them back.

When to Call an HVAC Technician

While DIY efforts can be effective in getting your AC running again, these systems are complex and sometimes necessitate professional service for repairs. Schedule a repair service if your troubleshooting didn’t work or you notice any of the following warning signs:

  • Low refrigerant: Often accompanied by ice build-up, low refrigerant may indicate a leak in the system.

  • Malfunctioning blower fan: If your blower fan continues to make strange sounds or isn’t running at all, it requires a professional service and potentially replacement.

  • Damaged ductwork: An HVAC technician can thoroughly examine your ductwork to identify and repair blockages, leaks, or other damage.

  • Repeated breaker trips: An occasional breaker trip is normal, but repeated incidents indicate bigger electrical issues and require a qualified professional.

  • Bad thermostat: A technician can assist whether your thermostat’s wiring needs repair or the entire unit needs replacing.

Why Professional AC Repairs Matter

AC systems are complex, and some repairs require advanced skills and knowledge. Attempting a DIY can result in further damage to your system, delayed repairs, increased repair costs, and a decreased AC system lifespan. Some parts of your system, such as refrigerant or electrical circuits, are hazardous and can pose significant risk of injury.

A professional and licensed HVAC technician possesses the experience and industry-standard knowledge to safely identify and handle your AC system’s repair needs. At Service Champions, we offer up-front pricing, financing options, and 100% guarantees on our work to ensure your AC runs as it should.

Get Same-Day AC Repair in Northern California

If your AC still isn’t cooling your home and you live in the East Bay, San Jose, Sacramento, or in our other California service areas, contact Service Champions Heating & Air Conditioning for expert AC repair.

Open 24/7, we’re available for same-day service and emergency repair to restore refreshingly cool air to your California home in no time. For repairs, maintenance, and other HVAC needs, contact us or book online today.

Frequently Asked Questions

My AC cycles on and off quickly. Is this a sign of a serious problem?

AC short-cycling is a common problem and can suggest a variety of minor or serious underlying issues. A technician can accurately diagnose the cause.

I can see ice on my AC unit. Should I turn it off and call an HVAC technician?

Several issues can cause ice to form on your AC unit. You can turn it off and try minor fixes, such as replacing the air filter, allow the unit to thaw, then restart it. If the issue persists, turn off the AC system and call an HVAC technician for professional diagnosis and repair.

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