Why is My Heating System Blowing Cold Air?

When the cold weather sets in for the winter months, nothing becomes more important in the home than an efficient heating system. If it isn’t already on when you arrive home, it will be one of the first few things you’ll want to turn on. However, just because the heating system sprang into action doesn’t mean it is working properly. One of the signs that the heating system needs repair is when it is blowing cold air.

In this blog, we will discuss what leads to the heating system blowing cold air, how to troubleshoot this problem, and how to prevent it in the future. Read along with some tips and tricks from the region’s top heating repair techs of QRC HVAC & Refrigeration. 

How Does a Heating System Work Anyways?

Any heating system is a mechanical and gas or electric unit made up of multiple parts that come together to produce a cozy home environment. These components are divided into four functions: heating source, distribution systems, control mechanisms, and safety features. We will break down these functions and the parts that make them possible down below. 

1. Heating Source

The heating source is the main, central component of any heating system that is responsible for generating heat. Most commonly, the heating source is either a furnace or boiler. 

• Furnace: Powered by various types of fuel like natural gas, oil, propane, or electricity
• Boiler: A hydronic heating system that boils water and circulates it through radiators, baseboard heaters, or radiant floor systems to heat a home. 

2. Distribution Systems

When the heat is generated, it must be sent through the house by a distribution system like ductwork, radiators or baseboard heaters, or heat exchangers. 

• Ductwork: Most common in central heating systems, ductwork carries warm air from the furnace or heat exchanger to different rooms in the building.
• Radiators or Baseboard Heaters: If your heating system is a boiler, it will need a set of radiators or baseboard heaters to circulate steam and warm the surrounding space. 
• Heat Exchangers: Heating systems that are powered by geothermal heat pumps use heat exchangers that transfer heat from one place to another. 
• Air filters and blower motors: In air-forced systems, the heat is pushed through air filters to ensure that only clean air is circulating through the home. The heat is pushed through these filters with the help of blower motors and fans. 

3. Control Mechanisms

Any heating or air conditioning system requires a control mechanism to signal it to begin working to bring the needed temperatures to the house. This control mechanism is typically a thermostat, which is built with sensors that detect the temperature in the home and make the heating system begin its work. 

4. Safety Features

Each heating system will have safety features that prevent it from creating hazardous situations. 

• Pressure Valves: These valves are found in boilers and are designed to regulate and prevent the pressure within a boiler. These keeps the system from exploding. 
• Temperature Limits: Many heating systems have limits on how high the temperatures can be, preventing the system from overheating. 
• Emergency Shut-off Mechanisms: These mechanisms signal the heating system to shut down when they sense a malfunction that poses a threat to safety. 

All of these parts come together seamlessly to create those needed temperatures of warmth during the cold winter months. When the thermostat is turned on, the heat is generated in the boiler or furnace and then distributed through the home with the help of the attached distribution systems. The safety features and thermostat respond as needed when the needed temperature is achieved or when the system faces some kind of safety challenge like overheating. 

Possible Causes for Cold Air & How to Troubleshoot Them

As we can tell heating systems are complex machines with many parts. For this reason, knowing what to do to fix the issue of them blowing cold air isn’t always straightforward. We’ve outlined the most common reasons for this problem and provided our top troubleshooting tips below. 

Thermostat Issues

Since the thermostat is in, charge of signaling the heating system to begin working, when the temperatures are not at the preset level, any malfunction with it can cause the entire system to malfunction as a whole. Dead batteries or an outdated thermostat can quickly lead you to believe that there is an issue with your heating system. Here’s what you can do to fix the issue of dead batteries:

1. Locate the thermostat in your home and lift the case cover where the batteries are stored.
2. Replace the batteries and put the cover back on.
3. Turn the thermostat back on to see if the replacement of batteries worked.

If you find that even replacing the batteries doesn’t help the thermostat turn on, you may need to clean it as well. If that doesn’t work, consider replacing the thermostat, especially if it is old. Also, take the steps to check the circuit breaker to ensure that the heating system is on and to reset it if necessary.

Pilot Light or Ignition Problems

If your heating system is a furnace that isn’t generating warm air, there may be a problem with the pilot light or ignition system. If the pilot light goes out, it will lead to the heating system blowing cold air instead of the warm air you want. Here’s what you need to do:

1. Locate the furnace in your home and find the pilot light on it. 
2. If you find that there is no flame, you will need to relight it. 
3. Find the manufacturer’s instructions for relighting the pilot light and see if that works to restore the heat. 

Sometimes, cleaning the pilot light or ignitor helps as dust and other debris can prevent the furnace from springing into action. 

Airflow and Duct Issues

The heating system blowing cold air can also be an issue of airflow and ductwork issues. If the heating is inconsistent throughout the home, there may be cracks or gaps in the ductwork that cause the air to escape before hitting the air filters and vents. This issue would have to be resolved by a professional HVAC repair tech. 

Airflow problems can also be caused by a dirty air filter and this problem can be rectified by replacing it with a clean one: 

1. Locate the air filter that is normally located near the air handler, heating unit, or along a wall. 
2. Remove the cover and the old filter. 
3. Place a new filter in place of the old one and secure the cover back in its place. 
4. Turn the heater on to check if airflow improves. 

Malfunctioning Heat Exchanger

A faulty heat exchanger can result in extensive and expensive heating system repairs. Here are some troubleshooting steps you can take: 

1. Turn off the heating system to ensure your safety
2. Check the heat exchanger for signs of damage like cracks and discoloration. 
3. If you find a small amount of soot, you can gently clean it off with a soft bristle brush. 

If there are large amounts of soot or signs of damage, you will need to get in touch with a professional heating repair technician for further assistance. 

How to Prevent Cold Air in a Heating System

By now, you’re probably wondering what you can do to avoid the issue of the heating system blowing cold air. After all, who has time for these problems? The seasoned heating repair technicians at QRC are in full agreement that most repair issues can be avoided by following some basic maintenance tips as outlined below: 

• Take the time to inspect and clean or change air filters at least every 90 days
• Keep the area around your heating system clean
• Make sure that the pilot light, thermostat, and other components of your heating system are always clean. 
• Schedule a routine maintenance service with your heating repair tech at least once before the cold season arrives. 

Regular maintenance services allow heating repair techs the chance to catch problems early on before they grow into bigger problems. 

Is Your Heater Not Blowing Warm Air?

If you’ve found yourself stuck in the cold with no heat, call QRC HVAC & Refrigeration for prompt and professional repair services. Our seasoned and skilled technicians have seen just about every problem and nothing is too challenging for us. With our help, your furnace or boiler will be back to producing that coziness you deserve. Contact us today and schedule your service.