AC Troubleshooting: Why Is My Houston House Not Cooling Properly?

Is your Houston home’s air conditioner not keeping your home as cool as it should? When those hot and humid Houston summers hit, a malfunctioning AC unit can make your home miserable. But before calling in the pros, there are a few DIY troubleshooting steps you can take to diagnose common AC problems.

With some basic mechanical skills and AC knowledge, you may be able to identify and fix the issue on your own. Read on to learn the top reasons your Houston house isn’t cooling properly, and how to troubleshoot each one.

Why Your Houston Home Isn’t Cooling

There are several possible reasons why your Houston home’s AC system may not be cooling properly:

1. Refrigerant Leak

One of the most common reasons an AC stops cooling effectively is due to a refrigerant leak. AC units require refrigerant to cool and dehumidify the air. The refrigerant absorbs heat from inside your home and moves it outside.

Over time, refrigerant can leak due to cracks, faulty seals, or loose fittings. A low refrigerant level reduces your AC’s ability to remove heat and humidity. Signs of a leak include:

• Higher electric bills: Low refrigerant levels make your AC work harder to try to cool your home, using more electricity.
• System runs constantly: To try to reach the target temperature, the AC unit will run for longer periods of time without shutting off.
• Little or no cooling: As refrigerant leaks out, cooling performance gradually declines. Eventually the AC may not seem to be blowing any cold air.
• Frost or ice on vents: A refrigerant leak can cause the evaporator coils to freeze over, leading to ice buildup on the external AC vents.

If you suspect a refrigerant leak, contact a licensed HVAC technician to test for leaks using specialized tools. They can pinpoint the location of the leak and recharge the refrigerant once any repairs are made.

2. Dirty Air Filter

Air filters play a crucial role in HVAC efficiency. As air passes through the filter, it traps dust, dirt, pollen and other particles before they can circulate through your home. But over time, air filters get clogged with debris.

A dirty filter restricts proper airflow, making your system work harder to push air through the restricted filter. This strains the blower motor and reduces cooling capacity.

Inspect your filter each month and replace it as needed, especially during high usage months. Many experts recommend upgrading to a high-efficiency pleated filter, which does a better job trapping particles while maintaining good airflow.

3. Frozen Evaporator Coil

The evaporator coil is responsible for absorbing heat from your home’s air to lower temperatures. But if dirt, dust and debris accumulate on the coil fins, it can’t absorb heat effectively. The coil may also freeze over if the refrigerant level is too low.

A frozen coil blocks proper airflow and stops your AC from cooling. Signs include:

• Lack of cold air from vents, even when the unit is running
• Frozen evaporator coil, visible as a layer of frost/ice around the copper lines
• Blower fan may stop working due to frozen ice

Turn off your AC unit immediately if you suspect a frozen coil. Call an HVAC technician to inspect the issue and rule out refrigerant leaks or other problems. Proper defrosting may require a professional.

4. Broken Fan Belt/Motor

The blower fan is what pushes cooled air through your home’s ductwork. If the fan belt connecting the motor to blower breaks, or the motor itself fails, the fan will stop spinning. This cuts off the airflow completely.

Warning signs include:

• Little to no air coming from vents
• Squeaking, grinding or buzzing noises
• Burning rubber smell from fan motor

Shut off your AC unit to prevent further damage. Replacing a broken fan belt is usually a simple DIY fix. But if the motor itself is broken, you’ll need a professional AC technician for repairs.

5. Faulty Thermostat

Your thermostat acts as the brain, monitoring temperatures and telling your AC when to turn on/off. If it’s malfunctioning, your unit can’t maintain the right temperature.

Problems include:

• Inaccurate temperature readings
• Failure to turn on AC when needed
• Short cycling (turning on and off rapidly)
• Unresponsive display screen
• Strange readings (e.g. -50°F)

Try rebooting the thermostat by turning off power at the breaker box for 30 seconds. If issues persist, replace old thermostats with a new programmable or smart thermostat.

6. Low Refrigerant Pressure

For cooling to occur, the AC system needs adequate pressure to cycle the refrigerant through the evaporator and condenser coils. Low pressure reduces the refrigerant’s ability to absorb and remove heat.

Causes of low refrigerant pressure:

• Refrigerant leaks (as discussed earlier)
• Restriction in the refrigerant lines
• Problem with the expansion valve or capillary tube
• Blocked condenser coil
• Compressor failure

Any of these require a technician to diagnose and fix. They’ll check for leaks and obstructions before recharging the refrigerant.

7. Blocked Drain Line

As hot humid outdoor air blows across your cold evaporator coil, condensation accumulates. This drips down into a drain pan and exits via a drain line.

If the drain line gets clogged with algae, mold or debris, the drain pan fills up and overflows. This water spillage can prevent proper airflow and lead to mold growth in ducts. Signs of a blocked drain line include:

• Water leaking from the overflow drain outlet
• Excess humidity in your home
• Moldy smell from vents
• Water damage on walls/ceilings near AC equipment

Try pouring a drain cleaner down the line to clear the clog. You can also use a stiff wire to poke through debris. Prevent future clogs by pouring bleach or vinegar down the line annually.

8. Wrong-Sized AC Unit

If your AC unit is too small for your home, it won€™t be able to keep up with the cooling demand. Oversized units also cause problems by short cycling on and off.

Signs you need a properly sized unit:

• AC runs all day but never reaches target temp
• House only cools when AC first turns on
• AC cycles on/off frequently

Have an HVAC pro assess your home’s needs and recommend right-sized replacement units if needed. Installing a variable speed AC can help better match cooling output to demand.

DIY AC Troubleshooting Tips

Before calling for service, try these basic troubleshooting steps:

• Check the thermostat settings to make sure cooling mode is turned on and temperature is set below room temp.
• Inspect the outdoor AC unit for debris blocking airflow. Remove leaves, grass clippings, etc.
• Clean the condenser coils if they are clogged with dirt and dust.
• Replace the air filter if it€™s visibly dirty.
• Make sure nothing is blocking the indoor air vents. Move furniture if needed.
• Check that air is coming out of vents. If not, check the fan belt.
• Listen for odd noises that may indicate a failed fan or motor.
• Monitor system pressures using AC gauges to check for leaks.
• Inspect the evaporator coil for ice buildup indicating a frozen coil or refrigerant issue.

When to Call a Professional

While some AC problems can be DIY fixes, more serious issues require a trained HVAC technician:

• Refrigerant leaks
• Frozen evaporator coils
• Faulty components like compressors, valves, motors
• Inadequately sized AC system
• Mold contamination or water damage
• Electrical issues with wiring, capacitors, contactors
• Strange noises indicating a broken component
• Low refrigerant pressures
• Thermostat malfunctions

A qualified AC company like Turbo Home Services has the skills, experience and tools to accurately diagnose any cooling issues. They can pinpoint the root cause and make professional repairs to restore cooling comfort.

Our technicians are highly trained in all makes and models. We stock parts on our truck so many repairs can be made quickly without waiting. We even offer 24/7 emergency AC repair when you need it most.

Beat the Houston Heat with a High-Performance AC

Don€™t let your home€™s AC issues leave you sweltering this summer. With some basic troubleshooting, you can identify problems before they cause serious equipment damage or sky-high utility bills. But for complex repairs, trust our Houston AC experts at Turbo Home Services. Call (281) 626-5938 or visit https://turbohomeservices.com/contact-us/ to schedule service. We€™ll get your system back to peak performance so you can stay cool in the Houston heat.