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Furnace Blowing Cold Air? Here’s Why

heater blowing cold air

As the temperature drops and the winter chill sets in, a reliable and efficient heating system is essential to keep your home warm and comfortable. But what do you do when your furnace suddenly starts blowing cold air instead of hot air? In this blog, we’ll delve into the common reasons why your furnace might be blowing cold air and offer insights into how to troubleshoot and address these issues.

If you’re experiencing issues with your furnace blowing cold air, the Carrollton furnace repair experts at Lex Air are here to help. We offer the residents of Carrollton, TX, and the surrounding area a variety of HVAC heating services, including furnace repair, replacement, installation, and maintenance.

We won’t leave you out in the cold–call us at (972) 217-8955 or contact us online to schedule our services or to learn more about what we can do for you and your home. 

Why Does My Heater Blow Cold Air?

Furnaces are designed to provide warm air for your home, but sometimes, they may unexpectedly start blowing cold air rather than hot air. This can be due to a variety of reasons, many of which are caused by a lack of regular maintenance. Luckily, some of these can be solved with some minor troubleshooting. Others, however, are the result of mechanical issues or broken parts. These issues will need to be addressed by an experienced HVAC professional. 

why is my furnace blowing cold air

Common Causes of a Furnace Blowing Cold Air

A furnace blowing cold air can be caused by various factors, ranging from simple thermostat settings to more complex issues with your heating system’s components. By understanding these common reasons, you can troubleshoot the problem and determine whether it’s something you can fix yourself or if it requires professional assistance.

Thermostat Settings

One of the most common reasons for a furnace to blow cold air is incorrect thermostat settings. It’s easy to accidentally set your thermostat to the “cool” mode or adjust the temperature lower than you intended, which can trigger your air conditioner to run rather than your furnace. 

Always double-check that your thermostat is set to the “heat” mode and that the temperature setting is at your desired level. This simple step can save you from the discomfort of cold air blowing through your vents and potentially unnecessary service calls.

Overheating Furnace

Another reason your furnace may be blowing cold air is because it is overheating. Furnaces have built-in safety mechanisms that shut them down if they detect excessive heat. This can happen if the air filter or condensate drain line is clogged, obstructing proper airflow and causing the furnace’s heat exchanger to work harder. When it overheats, it may shut down temporarily to prevent damage, leading to cold air blowing from the vents.

Pilot Light or Ignition Problems

For gas furnaces, a malfunctioning pilot light or ignition system can be the culprit behind your cold air problem. Pilot lights are responsible for igniting the gas to produce hot air. If the pilot light is out, or the ignition system is malfunctioning, the furnace may struggle to generate warmth. 

furnace not kicking on when temp drops

Dirty Air Filter

Your heating system may also be malfunctioning as a result of a clogged air filter. When your furnace’s air filter becomes clogged with dust, debris, and other particles, it obstructs the airflow, making it difficult for the system to heat your home efficiently. The reduced airflow can also lead to overheating, as mentioned above, which could cause the furnace’s safety mechanism to kick in and the system to blow cold air. 

Ductwork Leaks

Ductwork plays a vital role in distributing warm air throughout your home. If there are leaks or gaps in your ducts, cold outside air can infiltrate the system, mixing with the warm air produced by your furnace. These leaking ducts can make it feel like your furnace is producing cool air, decreasing comfort and warmth.

Fuel Supply Issues

Gas furnaces require a consistent and adequate supply of fuel in order to produce enough heat to warm your home. If there are issues with your natural gas supply, such as low gas pressure, a blockage in the gas line, or problems with the gas valve, your furnace may struggle to ignite and produce warm air. 

Faulty Flame Sensor

Another reason your gas furnace may be blowing cold air is that your flame sensor is broken or faulty. The flame sensor is responsible for ensuring that the gas burner remains ignited when producing heat. If the sensor malfunctions or becomes covered in soot or debris, it may signal the furnace to shut off, preventing the production of warm air.

causes of furnace blowing cold air

Troubleshooting Steps for Heater Blowing Cold Air

In the winter months, you often need all the hot air you can get. If your furnace is blowing cold air, try these troubleshooting steps to help identify and potentially resolve the issue. 

  • Check thermostat settings
  • Inspect air ducts 
  • Change clogged air filters
  • Clear condensate drain lines
  • Check pilot light
  • Check fuel supply
  • Clean flame sensor
  • Reset furnace

If these troubleshooting steps don’t solve the problem, or they don’t help you identify the problem, you should contact a local furnace technician. Qualified HVAC professionals can diagnose and address more complex issues, ensuring your heating system operates efficiently and safely.

When to Call a Professional for Furnace Repair

While some furnace issues can be addressed with simple troubleshooting steps, there are times when it’s essential to enlist the expertise of a professional technician. Calling in an HVAC professional for furnace repair is crucial not only for ensuring your heating system operates safely, but also for resolving complex problems that may be beyond your DIY capabilities.

You should call an HVAC technician if you notice:

Remember that attempting to repair a furnace without the necessary knowledge and expertise can be dangerous and may lead to further damage or safety hazards. Professional technicians have the training, experience, and tools to diagnose and repair furnace problems efficiently and safely. Regular furnace maintenance by a professional can also help prevent issues and ensure your heating system operates at its best, keeping your home warm and comfortable throughout the winter.

furnace blowing cold air

How Our Furnace Repair Techs at Lex Can Help

At Lex Air, we understand that a malfunctioning furnace or heating system can be a major inconvenience, especially when the temperature drops. That’s why we’re committed to providing top-notch HVAC services to our valued customers in Carrollton, TX, and the surrounding areas. When you choose Lex, you’re choosing a team of highly skilled and experienced professionals dedicated to keeping your home warm, comfortable, and energy-efficient.

We offer a variety of Carrollton heating services, ensuring you and your family have a steady supply of heated air all winter long. Whether you’re in need of heater repair for your pre-existing heating system, or you need a brand-new heater installation, we’re here to provide you with the services you need. 

The Importance of Preventative Furnace Maintenance

Preventative furnace maintenance is more than just a recommended practice; it’s a crucial step in ensuring the efficient, safe, and reliable operation of your HVAC system. Whether you have a gas furnace or an electric furnace, it’s important to schedule regular heater maintenance on your system.

Regular heating maintenance from an HVAC professional not only helps you avoid unexpected breakdowns during the coldest months of the year but also extends the lifespan of your furnace. It also helps improve your system’s energy efficiency, allowing you to save money on your monthly electricity bill without sacrificing your comfort throughout the heating season.

At Lex Air Conditioning and Heating, we believe in the importance of regular preventative maintenance for your heating and cooling systems. That’s why we offer our valued clients the opportunity to join our exclusive Cool Club. As a Cool Club member, you’ll enjoy the peace of mind that comes with yearly HVAC maintenance visits, ensuring that your HVAC system operates at its best throughout the year.

Beyond the regular maintenance, Cool Club members also receive priority scheduling, which means you’ll have top priority for service appointments, especially during peak seasons. Additionally, members can take advantage of exclusive discounts and special offers, helping you save on repairs and upgrades. Lex Air’s Cool Club is designed to provide our clients with the highest level of care and convenience, ensuring that your home remains comfortable and efficient.

why is my furnace blowing cold air

Call Lex for 24/7 Heating Repair and Service

Don’t let a malfunctioning heating system disrupt your comfort and peace of mind. If your furnace is blowing cold air, call a qualified HVAC technician at Lex Air. Our team is here to provide you with 24/7 heating repair and service, ensuring that your furnace or heating system is always there to keep you warm when you need it most. 

Our commitment to excellence, years of experience, and dedication to customer satisfaction make us the go-to choice for all your HVAC needs. We’re not just here to fix problems; we’re here to prevent them, enhance your system’s efficiency, and help you save on energy costs.

Whether you need emergency heating repairs, preventative maintenance, system upgrades, or any other HVAC services, we’re just a phone call away. So call us at (972) 217-8955 or contact us online to schedule our services or to learn more about what we do.