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Why is My Furnace Blowing Cold Air?


September 13, 2023


While it’s still warm here in Florida, the last thing you want is to be left shivering indoors due to a furnace blowing cold air when it starts getting chilly outside. It’s a situation that can leave you feeling frustrated and uncomfortable, especially when you’re relying on your heating system to keep your home warm and cozy. 

In this blog, we’ll dive into the common culprits behind this issue and explore possible solutions to ensure your furnace operates at its best, providing you with the warmth you need during the cold season. So, let’s unravel the mystery of why your furnace might be blowing cold air and find the answers to keep you snug all winter long.

How Does a Furnace Work?

A furnace is a crucial component of many heating systems, and its primary function is to generate and distribute warm air throughout a building, typically a home or commercial space. A furnace works by heating air through a combustion process, circulating the heated air through a building’s ductwork, and distributing it to various rooms to maintain a comfortable indoor temperature. Proper maintenance and regular inspections are essential to ensure the furnace operates efficiently and safely.

What Are the Reasons Your Furnace is Blowing Cold Air?

If your furnace is blowing cold air instead of warm air, several potential reasons could be causing this issue. It’s essential to identify the underlying problem to restore proper heating. Here are some common reasons your furnace may be blowing cold air:

Thermostat Settings

Check the thermostat to ensure it is set to the “heat” mode and the desired temperature. Sometimes, the thermostat may accidentally be set to “cool” or “fan-only” mode.

Pilot Light or Ignition Issues

If you have a gas furnace, a malfunctioning pilot light or ignition system can prevent the furnace from heating. This might require professional repair.

Dirty or Clogged Air Filters

A dirty or clogged air filter can restrict airflow, causing the furnace to overheat and shut down the burners prematurely. Replace or clean the filter regularly to avoid this issue.

Gas Supply Issues

If you have a gas furnace, an interruption in the gas supply, such as a closed gas valve or a gas leak, can prevent the furnace from producing heat. Gas supply issues should be addressed immediately by a qualified technician.

Malfunctioning Thermostat

A faulty thermostat can miscommunicate with your furnace, causing it to turn off before reaching the desired temperature.

Dirty or Blocked Heat Exchanger

A dirty or blocked heat exchanger can impede the transfer of heat, causing the furnace to blow cold air. Regular maintenance can help prevent this problem.

Blocked Vents or Registers

Ensure that all vents and registers in your home are open and unobstructed to allow proper airflow.

If your furnace is blowing cold air, it’s best to consult a qualified HVAC technician to diagnose and address the specific issue. Regular maintenance and prompt repairs can help prevent such problems and ensure your furnace operates efficiently and reliably.

Furnace Repair in Jacksonville and St. Augustine

If your furnace is blowing cold air and leaving you in the cold, Lickety-Split is here to bring back the warmth to your home. Our team of skilled technicians has the expertise to diagnose and repair a wide range of furnace issues, ensuring your heating system operates at its best. Contact Lickety-Split for prompt, reliable furnace repair services and enjoy the cozy warmth you deserve all winter long.


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