If your furnace is blowing cold air, it can be a real hassle. Not only does it mean that you’re not getting the warmth and comfort you need in your home during winter, but it can also be a sign that there’s something wrong with your furnace and it needs to be repaired. In this blog post, we will discuss common reasons that a furnace would start blowing cold air – and what you can do about it!
Contents
How Does A Furnace Work?
A furnace is a household appliance that is used to heat up a room or house.
The furnace works by burning fuel, such as natural gas, propane, oil, or wood. The heat from the burning fuel is then used to warm up the air in the furnace and distribute it around the house.
Furnaces can be either forced-air or gravity-fed. A forced-air furnace uses a fan to push the heated air through the ducts and into the rooms of the house. A gravity-fed furnace uses the natural rising of hot air to circulate it around the house.
Most furnaces will have a thermostat that is used to control the temperature of the furnace. The thermostat will turn the furnace on and off as needed to maintain the desired temperature.
Furnaces can also be controlled by a central heating system. A central heating system is a system that controls multiple appliances, such as the furnace, HVAC system, and water heater.
Furnaces are typically located in the basement of a house. However, they can also be located in an attic or garage. If you have a forced-air furnace, you will need to have ductwork installed in your home in order to circulate the heated air. Gravity-fed furnaces do not require ductwork.
Why Is My Furnace Blowing Cold Air?
A furnace blowing cold air is a common problem that homeowners face. There are many possible causes for this, but the most common ones are listed below.
Clogged Furnace Filter
A dirty air filter can stop a furnace from working well and cause it to blow cold air. A clogged filter can cause the furnace to work harder than it needs to, which can lead to it blowing cold air. Make sure to clean or replace your furnace filters regularly to prevent this from happening. Restricted airflow can make the heater blow cold air.
- The first step is to check your furnace filter and replace it if it’s dirty. A clean filter will help your furnace run more efficiently and prevent it from blowing cold air.
- If you have a reusable filter, simply rinse it off with warm water and soap. Let the filter dry completely before putting it back in your furnace. If you have a disposable filter, simply replace it with a new one.
- Be sure to check your furnace filter regularly and replace it as needed to keep your furnace running properly. By doing so, you can avoid having to deal with a cold blast of air when you least expect it!
- Most furnaces have a little door that provides easy access to the filter. Simply open the door, remove the old filter, and insert a new one. Make sure the new filter is facing the correct direction before closing the door.
If you’re not sure how to change your furnace filter, consult your furnace’s owner’s manual or contact a professional for assistance. Either way, it’s important to keep your furnace filter clean to prevent cold air from blowing into your home.
Clogged Vents
Clogged vents can make a furnace blow cold air because the air cannot circulate well and so the heat is not distributed evenly. This means that the furnace will not be able to heat your home as well as it should, and you may end up with cold air blowing from your vents.
To clean the vents, remove the vent cover. Then use a vacuum cleaner or brush to clean the inside of the vent. If cleaning the vents doesn’t solve the problem, you may need to call a professional for help.
Thermostat Settings
A faulty thermostat can cause the furnace to blow cold air. Make sure to check your thermostat regularly and replace it if it is not working properly.
The thermostat controls how hot or cold your house gets, so if it is set too low or too high, it can cause the furnace to blow cold air. If the thermostat setting is too low, the furnace will turn on and off more frequently, which can cause it to blow cold air. If the thermostat is set too high, the furnace will run for a longer period of time, which can also cause it to blow cold air.
If you think that the thermostat might be the problem, you should first try adjusting it. If that doesn’t work, you should call a heating technician to take a look at your furnace. They will be able to diagnose the problem and make any necessary repairs.
Dirty Flame Sensor
A dirty flame sensor can cause a furnace to blow cold air. This is because the dirty sensor will not be able to read the heat from the flames correctly, which will make the furnace think that it is too cold and will blow cold air instead of heating your home.
To clean your flame detector, you will need a screwdriver and some rubbing alcohol. First, unscrew the sensor from the furnace. Next, dip a cloth in the rubbing alcohol and wipe down the sensor. Be sure to get all of the dirt and grime off of the sensor so that it can work correctly. Finally, screw the sensor back into place and turn on your furnace. You should now have warm air coming out of your vents!
If you have any questions about cleaning flame detectors or if you need help with anything else related to your furnace, be sure to contact a professional.
Overheating Furnace Safety Mode
The furnace could be blowing cool air instead of hot because it is switched to its protection mode, which is a safety measure. This safety feature is designed to protect your furnace from overheating. If the furnace overheats, the safety mode kicks in and blows cooler or warm air instead of hot.
If your furnace is blowing cooler air, it’s important to find out why. It could be a simple fix, like adjusting the thermostat. Or it could be a more serious problem, like a problem with the furnace’s heat exchanger. In this case, you’ll need to call a furnace technician.
Pilot Light Problems
A pilot light is a small flame that is lit in order to start a larger fire. In older furnaces, pilot lights are used to ignite the gas that is used to heat the home. If the furnace blows cold air, it may be because the pilot light is not working properly.
There are a few things that you can do in order to fix a pilot light that is not working. The first thing that you should do is check the gas supply. If the gas is turned off, then the pilot light will not be able to ignite. You should also check the batteries in the thermostat. If the batteries are low, then the furnace may not be getting the signal to turn on. Finally, you should clean any dirt or debris from around the pilot light. This will ensure that there is enough oxygen for the flame to stay lit.
If you have tried all of these things and the pilot light still will not stay lit, then you may need to call a professional for help. A certified technician can come to your home and diagnose the problem. They may need to replace the pilot light assembly or other parts in order to get your furnace up and running again.
Your furnace is an important part of your home, and you should make sure that it is working properly. A pilot light that won’t stay lit can be a sign of a bigger problem. If you have tried everything and the pilot light still won’t stay lit, then you should call a professional for help. A certified technician can come to your home and diagnose the problem. They may need to replace the pilot light assembly or other parts in order to get your furnace up and running again.
Gas Supply Issues
A low supply of gas in the home can cause the furnace to blow cold air because there is not enough fuel to generate heat. Without a sufficient supply of gas, the furnace will not be able to produce enough heat to warm the home, resulting in cold air blowing from the vents. If you notice that your furnace is blowing cold air, check the gas supply to ensure that there is enough fuel for the furnace to generate heat.
Blocked Airflow
Another possibility is that there is something restricting airflow to your furnace. A build-up of dust and debris around your furnace restricts airflow. To fix this, you’ll need to clean around your furnace and make sure there’s nothing blocking airflow to it. Again, if this doesn’t solve the problem, you may need to call a professional.
Clogged Condensate Drain Lines
A condensate line is a pipe that carries water vapor and other pollutants from the furnace to the outdoors and is a feature of more modern furnaces.
The condensate line is an important part of your furnace, and it is important to keep it in good working order. If the condensate line becomes clogged, it can cause water damage to your home.
Also, if the condensate lines are clogged, the furnace will not be able to function properly and will blow cold air.
There are a few things you can do to clean the condensate lines. One is to pour a cup of bleach down the drain line once a month. You can also use a shop vac to suck out any debris that might be clogging the line. If neither of these methods works, you may need to call an HVAC professional to clean the lines for you.
The most important thing to remember is that if the condensate lines are not clear, your furnace will not work properly and could end up costing you more money in repairs. Be sure to keep an eye on them and clean them regularly to avoid any problems.
Damaged Ductwork
Ductwork damage can cause the furnace to blow cold air by disrupting airflow and preventing the furnace from heating the air properly. This can cause the furnace to work harder and overheat, leading to a decrease in efficiency and an increase in energy bills.
If you suspect that your ductwork may be damaged, it’s important to have it inspected by a professional. Ductwork repair is not a do-it-yourself job, and attempting to repair it yourself could make the problem worse. A professional furnace repair contractor will be able to assess the damage and recommend the best course of action.
Maintenance
Improper installation or lack of maintenance can also lead to furnace and air conditioning problems, so be sure to keep up with both. otherwise, you’ll likely be dealing with a cold house this winter!
Conclusion
There could be a number of reasons why your furnace is blowing cold air, from a dirty filter to a problem with the wiring. If you’re uncomfortable investigating the issue yourself, it may be time to call in a professional. A technician can help you determine what’s causing the problem and fix it so you can start enjoying warm winters again!
