When the winter is underway, keeping your home warm requires occasional maintenance of your furnace. A common circumstance that many homeowners notice when temperatures drop is that the furnace is blowing out cooler air than it should. While this isn’t necessarily cause for panic, it’s definitely something you should take care of in order to have a more comfortable winter.
Your furnace blowing cold air instead of warm may be the first sign that it is not functioning properly. If your furnace is having issues, your home can quickly become uncomfortable, especially when the outdoor temperature is below freezing. This can also cause other issues, like freezing the pipes in your home. Before the next cold winter night, let’s explore some of the reasons your furnace is blowing cold air.
1. Thermostat Issues
One of the first things to consider when cold air is an issue is the temperature setting on the thermostat. Obviously, you want warm air, but if you have the thermostat set to “auto,” you could find that it releases cold air when the furnace is not actively trying to heat the space. Another common mistake that happens is when the thermostat is incorrectly set to “cool” rather than “heat.”
Also, make sure to check the batteries in your home’s thermostat to make sure they are working. Sometimes, the thermostat will quickly drain power from your batteries when there is a faulty or missing common wire, which is often referred to as the “C wire.” This wire delivers constant power to the thermostat, so if it’s malfunctioning or missing completely, this will cause a large amount of energy drain on the thermostat’s batteries.
Even with a perfectly functional C wire, circuitry issues can cause excessive draw on the thermostat’s batteries. In fact, when you’re getting low battery warnings, it could simply be giving a low battery warning without the batteries actually being low. You can check your batteries using a battery checker. You should also check the contacts on the battery to determine if there is any excess residue that might be preventing the thermostat from drawing the correct amount of power.
If the thermostat is set correctly, then the issue could be that the thermostat is not sending the correct messages to the circuit board. Perhaps the message is being sent to turn the blowers on instead of the burner. Since the circuit board is the brains of the furnace, you will want to make sure that annual maintenance takes place on it. The circuit board could have a simple malfunction that’s easy to fix, but something more serious like corrosion or water damage will need a professional solution.
2. Gas Issues
Check to ensure that you have gas in your furnace, and if the tank has a sufficient amount, make sure all of the valves that allow the gas to reach the furnace are in the correct position. If the gas is not to a certain height in the tank, chances are that the furnace will not function properly.
If the gas levels are fine, then the pilot light may not be able to ignite the furnace burners. If the supply of gas was lower than normal, there is a chance that the pilot light went out. If this is the case, you may need to relight the pilot light. If this does not work, it could be a bigger issue that a professional will need to look at. Many furnaces with a manufacture date of 2010 or after have igniters in use instead of a pilot light. If this is the case, these electronic devices can easily malfunction. If it has not received maintenance for years, it may be time to replace it.
Many of the furnaces that do not have a pilot light rely on a flame detector to heat the unit. If this is the case and the flame detector has dust covering it, then your furnace could blow cold air. Even if the air is not completely cold, the detector being unclean ensures that the heat coming out is not efficient, which means electric bills could be higher.
3. Airflow Issues
When the air does not flow well within the furnace, it is not going to heat your home as efficiently. Airflow may not be as good simply because of dirty air filters. A blocked air filter can cause the furnace to overheat. A simple solution to this is to check the filters, but if they have been in use for years, then consider replacing them.
Another piece of the furnace that can limit airflow when it is malfunctioning is the blower fan. This maintains a consistent temperature in your home, and if the air is not circulating properly, the blower fan could need repairs.
4. Air Duct Issues
Air ducts that leak or are not properly insulated can cool the air coming from the furnace before it reaches your living space. This cooling of the air not only makes your living space less comfortable but also potentially increases your energy bills. With poorly insulated ducts, the warm air becomes much cooler before it comes up through the vents into your home.
Ducts that are too small also tend to limit the airflow, which makes the air much cooler before it reaches the vents. Clogged vents within the home can also limit airflow and reduce the output of heat. Make sure that the vents in your home are clean at the beginning of the heating season. Having debris in the vents can be a hazard that could put your family at risk.
5. Overheating and Safety Measure Issues
There are a few things on heaters that can malfunction and cause the unit to overheat. The main thing that could overheat is the blower motor. This is what regulates the temperature in your home, keeping you comfortable as the temperatures drop outside. If it overheats, the air will become cold, and it will not circulate throughout the home as well.
There are safety precautions in place for all furnaces to make sure that nothing bad happens when you are heating your home. The limit switch is a part that ensures that the furnace is safe and does not overheat. It ensures that the temperature of the furnace remains within a safe range. When the switch determines that something is not working properly, it shuts off the heat, which makes cold air blow instead. If this switch is not manually reset, it could continue to blow out cold air.
Contact a Reliable Professional
At Perfect, Plumbing Heating & Air, we have been providing heating and cooling solutions since 1984. We also provide exceptional plumbing services in the Boise, ID area. We dedicate our time and energy to providing the best HVAC services in the region, and we strive to make sure your satisfaction with our work is our priority. If you need help determining what is wrong with your furnace, call us at Perfect, Plumbing Heating & Air today to schedule an inspection.
