AC not Cooling in the Houston area?

Is your AC not cooling down as it should, leaving you sweating and uncomfortable? Worry not, we have got you covered! In this comprehensive guide, we will walk you through the common causes of a house that refuses to cool down and provide you with effective solutions to restore your home’s comfort. Say goodbye to sweltering summers and hello to a perfectly chilled haven!

Understanding Why Your House Isn’t Cooling Down

A person adjusting the thermostat of an air conditioner

So, what could be behind your home’s refusal to cool down? Common causes include incorrect thermostat settings, dirty air filters, blocked airflow, frozen evaporator coils, condenser unit obstructions, refrigerant leaks, inadequate home insulation, and ventilation, among others. A malfunctioning air conditioner can create discomfort and frustration, especially during hot summer months. Identifying the root cause of the problem is the first step towards a cool and comfortable home.

It is essential to examine your thermostat first if your air conditioner is not cooling. Incorrect settings can lead to warm indoor air and an overworked AC system. If you have checked the thermostat and still face issues with your air conditioner not cooling, it’s time to dig deeper into potential causes.

The complexity of air conditioning systems can be overwhelming, but fear not! In the sections that follow, we will guide you through each potential cause of your house not cooling, offering easy-to-follow solutions to restore your home’s comfort. Let’s dive in!

Adjusting the Thermostat Settings

As mentioned earlier, an incorrect thermostat setting can be a prime culprit behind your house not cooling down. Before anything else, check if your thermostat is set to “cool” and adjusted to a lower temperature than the current room temperature. This will ensure your air conditioner is blowing cold air as expected.

If you find your thermostat set to “heat” or “continuous fan,” switch it back to cooling mode. Verify that the thermostat is functioning correctly and providing the desired indoor temperature. If not, potential remedies for a malfunctioning thermostat include replacing it or checking its settings and power source.

A low refrigerant level can also hinder your AC’s cooling capacity. If you suspect a refrigerant leak, you’ll need to call a professional for repair. Do not attempt to fix refrigerant leaks yourself, as it can be hazardous.

Cleaning or Replacing Dirty Air Filters

A person replacing an air filter

A dirty air filter can significantly impact your air conditioning system’s performance, leading to warm air being circulated instead of the desired cool air. A clogged filter, caused by an accumulation of dust and debris, can impede airflow and lead to overheating. In extreme cases, it may even cause your air conditioner to shut down.

To avoid these issues, inspect your air filter regularly. If it’s dirty, clean it using a vacuum or a soft brush. If the filter is too dirty to clean effectively, replace it. Not only will this help your air conditioner perform better, but it will also improve your indoor air quality by removing soil, pollen, and other airborne particles.

Keeping your air filters clean and free from debris ensures smooth airflow and prevents your evaporator coil from freezing, which is the most prevalent source of diminished cool air circulation. So, make it a habit to check and clean or replace your air filters regularly.

Inspecting and Clearing Blocked Airflow

Blocked air flow can lead to weak airflow, uneven cooling, strange noises, and drastically different temperatures between rooms. To ensure that your central air conditioner’s vents and ducts are not obstructed, inspect them for any furniture blocking the vents, dust, dirt, or debris.

If you find any obstructions, remove them with care. To confirm that your air conditioner is providing adequate airflow, activate the HVAC system and assess the air exiting the vents. Clearing blocked airflow not only improves your indoor air quality, but also enhances heat transfer, helping your air conditioner cool your home more efficiently.

Addressing Frozen Evaporator Coils

A frozen evaporator coil can hinder your air conditioner’s ability to cool your home. The evaporator coil is located inside the indoor unit, above the furnace. This coil facilitates heat transfer from the indoor air to the refrigerant which passes through it. When airflow is limited, the refrigerant will freeze, preventing the air conditioner from providing cold air.

Frozen evaporator coils can occur due to a decrease in refrigerant levels. If you suspect a frozen evaporator coil, you’ll need to call a professional for repair. Attempting to fix a frozen evaporator coil yourself can be dangerous and may lead to further damage.

Checking and Cleaning the Outdoor Condenser Unit

The outdoor condenser unit, also known as the outdoor unit, plays a crucial role in your air conditioning system’s performance, working in tandem with the indoor air handler unit. Dirt, grass, and other debris can accumulate on the condenser unit and impede its ability to cool your home efficiently. To check and clean the outdoor condenser unit, inspect the disconnect box for loose, damaged, or burnt wires. If you find any issues, call a professional for repair.

Next, examine the fan blades and motor for potential damage. Clearing dirt can help to unclog a condenser coil. Vacuuming the coil with a brush attachment or rinsing with a hose are other alternatives. Regular maintenance of the outdoor condenser unit can help prevent system shutdowns and improve the overall efficiency of your air conditioner.

Identifying Refrigerant Leaks

A refrigerant leak can cause your air conditioning system to stop cooling, run longer, damage the compressor, or shut down entirely. Decreased refrigerant levels result from freon leaks, which hinder effective heat transfer.

If you suspect a refrigerant leak, do not attempt to fix it yourself. Instead, call a professional for repair. Addressing refrigerant leaks promptly can help prevent further damage to your air conditioning system and restore its cooling capacity.

Improving Home Insulation and Ventilation

Inadequate home insulation can lead to air leakage around doors, windows, plumbing, and electrical outlets, as well as poor insulation in walls, attic, basement, or crawl space. This can cause cool air to escape and hot air to enter your house, diminishing your air conditioner’s cooling capacity.

Improving your home’s insulation and ventilation can help keep cool air in and hot air out, reducing energy bills and improving comfort. Attic ventilation is especially important for cooling down a house, as excessive heat buildup in the attic can lead to hot air entering the rest of the house and affecting your central air conditioner’s performance.

Considering AC System Upgrades

If your current air conditioning system is unable to adequately cool your living space, it may be prudent to consider replacing it with a new AC unit. When purchasing a new air conditioner, seek out the EnergyStar label and have a professional size and install the new system.

Correct sizing and installation are essential for providing optimal indoor comfort. If you are unsure whether you need a new HVAC system, contact an HVAC contractor for an assessment. Upgrading your AC system can help increase efficiency and save you money in the long run.

Preventative Maintenance for Optimal Cooling Performance

AC not cooling? An image showing a clean air filter, which is essential for house not cooling down prevention and optimal cooling performance.

Regular AC Maintenance is crucial to ensure that your air conditioning system functions properly and to prevent potential issues. A certified HVAC technician can identify areas of concern and components that should be replaced before they reach the end of their lifespan during maintenance.

During an AC tune-up, an HVAC specialist evaluates the necessary criteria for optimal airflow, examines refrigerant levels, and evaluates each mechanical component. Regular maintenance can help prevent issues such as bad capacitors and low voltage wires, avoiding the need for costly AC repairs.

Invest in preventative maintenance to keep your central air conditioner, central air conditioning system, and air conditioners running smoothly and your home comfortably cool.


In conclusion, a comfortable, cool home is within your reach by understanding the common causes of a house not cooling down and taking steps to address them. From adjusting thermostat settings to considering AC system upgrades, each solution plays a vital role in maintaining a comfortable living environment. Invest in preventative maintenance and follow our expert advice to enjoy a perfectly chilled haven, even during the hottest summer months.

  1. Energy Star – Proper AC Use and Maintenance: Energy Star Guide
    • Energy Star is a program run by the U.S. Environmental Protection Agency and U.S. Department of Energy that helps people save money and protect the environment through energy-efficient products. This link provides guidelines on the proper use and maintenance of air conditioners.
  2. U.S. Department of Energy – Air Conditioning: DOE – Air Conditioning
    • This link from the U.S. Department of Energy offers information on different types of air conditioning systems and energy-saving tips.
  3. ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) – Homeowner Resources: ASHRAE Resources
    • ASHRAE is a global society advancing human well-being through sustainable technology for the built environment. This link provides various resources for homeowners regarding heating, refrigeration, and air-conditioning.
  4. Consumer Reports – Best Air Conditioners of the Year: Consumer Reports AC Reviews
    • Consumer Reports is an independent, nonprofit organization that works side by side with consumers to create a fairer, safer, and healthier world. This link provides reviews and guides on the best air conditioners for those considering purchasing a new unit.
  5. EPA – Indoor Air Quality (IAQ): EPA Indoor Air Quality
    • This link from the Environmental Protection Agency provides information on indoor air quality, which is relevant when discussing air filters and the circulation of cool air inside homes.

Frequently Asked Questions

Why is my AC not cooling down in my house?

It appears that a clogged filter may be the cause of your AC not cooling down. When the filters become blocked, they restrict the air flow and the AC can’t efficiently cool your home.

To prevent this from happening, regularly clean or replace the filters to ensure your AC functions optimally.

Why is my AC not cooling enough on hot days?

It is likely that your AC needs a tune-up. Check if the air filters are dirty, the refrigerant level is low or components of the AC, such as the motor or evaporator coil, may be worn out. Regular maintenance can help improve the performance of an AC and ensure it runs reliably on hot days.

Should I turn off AC if it’s not cooling?

Based on the advice from answers, if your AC is not cooling and you’ve checked the thermostat and air filter to no avail, then it’s best to turn off your AC and seek professional help.

This way, you can avoid further damage to the system or other parts of your home.

What are the common causes of a house not cooling down?

Common issues causing a home not to cool down include incorrect thermostat settings, blocked air flow, refrigerant leaks, and dirty air filters. With these problems being relatively easy to diagnose and repair, it’s important to take action quickly to ensure the comfort of your home.

How often should I inspect and clean or replace my air filters?

To ensure your air filters are functioning properly, it is recommended to inspect and clean or replace them every 1-2 months.