What to Do When Your Furnace Blows Cold Air

Cold air blowing from your furnace can be especially frustrating during the winter. Whether you're enduring a cold snap or trying to keep your home comfortable, understanding why this happens and how to fix it is essential.

Knowing the underlying causes is crucial for maintaining your HVAC system’s performance. This knowledge cannot only prevent an uncomfortable home environment but can also help extend the lifespan of your furnace and air conditioning system.

In this blog, the Tiger Plumbing, Heating, & Air team explores common reasons why a furnace blows cold air and provides practical steps to prevent issues to keep your heating system operating efficiently all winter.

What Are the Key Components of a Furnace System?

Furnaces have several vital components that work together to heat and circulate air throughout your home. The key components include:

Burner

The burner is responsible for igniting the fuel (natural gas, propane, or oil) to produce heat. It mixes the fuel with air and ignites it to create a flame.

Heat Exchanger

The heat exchanger transfers heat generated by the burner to the air circulating through the furnace. It allows the air to be heated without coming into direct contact with the combustion gases.

Blower Fan

The blower fan circulates air over the heat exchanger and distributes the warm air through the ductwork into different rooms of the home.

Flue or Venting System

This system expels combustion gases produced during the heating process outside the home, ensuring safety by preventing harmful gases from entering the living space

Ignition System

This system ignites the burner. It can be a pilot light (a small flame that ignites the burner) or an electronic ignition system that lights the burner when needed.

Proper maintenance ensures your system runs efficiently, providing optimal heating without overworking. Regular checks on ignition systems and cleaning the furnace help maintain furnace efficiency and prevent system strain.

What Temperature Should You Set Your Thermostat to Avoid Overworking Your Furnace?

Setting the right temperature on your thermostat is key to avoiding unnecessary strain on your furnace. Experts recommend keeping your thermostat between 68°F and 72°F during winter when you're at home, ensuring your furnace doesn't work too hard to maintain a comfortable temperature.

Lowering the thermostat when you're asleep or away from home can also help reduce the load on your furnace while saving energy costs.

Another tip is to invest in a programmable thermostat, which allows you to schedule temperature adjustments based on your daily routine. By setting your thermostat to lower the temperature by 7-10 degrees for eight hours a day, you can significantly reduce your heating bill without compromising comfort.

Avoid setting the temperature too low, though. This can cause your furnace to cycle on and off more frequently, increasing wear and tear on the system.

What Are the Red Flags Indicating Potential Furnace Problems?

Identifying the early warning signs of furnace trouble can save you from unexpected breakdowns and expensive repairs. Common red flags include:

Strange Noises

If you hear rattling, banging, or squealing sounds from your furnace, these could be signs of loose or damaged components.

Uneven Heating

Similarly, if some rooms in your home are consistently colder than others, it may indicate an issue with your ductwork or the furnace's ability to distribute heat properly.

Frequent Cycling

When your furnace turns on and off too often, it can be another indicator of trouble. This could be due to a faulty thermostat, dirty filters, or an overheating furnace. If left unchecked, this constant cycling can lead to more severe mechanical issues and a furnace that stops working entirely.

Higher Than Normal Energy Bills

Monitoring your energy bills is also a good practice. A sudden spike in energy costs often indicates an inefficient furnace, which could be caused by dirty filters, blocked vents, or more serious issues such as a failing motor. 

Does Insulation Impact the Efficiency of Your Furnace?

Yes, insulation significantly impacts the efficiency of your furnace. Here's how:

1. Reduced Heat Loss: Proper insulation helps prevent heat from escaping your home. When your home is well-insulated, the furnace doesn’t have to work as hard to maintain the desired temperature, leading to lower energy consumption and reduced heating costs.

2. Improved Temperature Consistency: Insulation contributes to a more consistent indoor temperature. When heat is retained effectively, you’re less likely to experience drafts or cold spots, which can help the furnace operate more efficiently by reducing the need for constant adjustments.

3. Lower Energy Bills: With improved insulation, your furnace can run less frequently, which translates to lower energy bills. This is especially noticeable during the colder months when heating demands are higher.

4. Extended Furnace Lifespan: When a furnace operates more efficiently and less frequently, it experiences less wear and tear. This can extend the lifespan of the system, reducing the need for repairs or premature replacement.

5. Enhanced Comfort: Proper insulation enhances overall comfort by preventing heat loss. This means your furnace won’t have to work overtime to keep the space warm, resulting in a more comfortable living environment.

6. Environmental Benefits: Increased efficiency from improved insulation can lead to a reduction in fossil fuel consumption, contributing to a smaller carbon footprint and less environmental impact.

Investing in proper insulation is crucial for maximizing your furnace's efficiency, lowering energy costs, and ensuring a comfortable living environment.

What Steps Should You Take if Your Furnace Suddenly Malfunctions During a Cold Snap?

A furnace malfunction during a cold snap can be stressful, but there are immediate steps you can take to protect your home and family, including:

Check Your Settings

First, check your thermostat settings to ensure they're set to "heat" and the temperature is high enough for the furnace to engage.

Inspect the Filter

Inspect your air filters; dirty filters can block airflow and cause the system to shut down.

Consider the Breaker

If the furnace still doesn't work, check the circuit breaker to ensure it hasn't tripped.

If these basic troubleshooting steps don't resolve the issue, it's time to call a professional. In the meantime, take steps to keep your home warm by using space heaters, closing off unused rooms, and insulating windows and doors to prevent heat loss.

You can also use heavy blankets and wear layers to stay warm until your furnace is repaired.

How Tiger Plumbing, Heating, & Air Can Help When Your Furnace Blows Cold Air

When your furnace starts blowing cold air, it's essential to have a trusted HVAC specialist who can quickly diagnose and fix the issue.

At Tiger Plumbing, Heating, & Air, we are fully equipped to handle all aspects of furnace maintenance and repair, ensuring your home stays comfortable throughout the colder months.

With over 20 years of experience and a team of expert technicians, we can address common issues like faulty thermostats, clogged filters, or more serious mechanical problems, providing fast and efficient solutions to keep your furnace running smoothly.

Whether you're concerned about overworking your furnace, improving your home's insulation for better efficiency, or addressing plumbing issues, our expertise covers all your needs.

We offer routine maintenance, emergency repairs, and system upgrades to ensure your heating, cooling, and plumbing systems are always performing at their best.

Our team is here to support you with all your HVAC and plumbing needs. Contact us today for more information or to schedule a service.