All Rights Reserved. With electronic ignition systems, cold air could be caused by an electrical issue or if parts need to be adjusted or replaced. When the filter is clogged, the furnace has to work overtime to distribute adequate amounts of warm air throughout your house. When it’s cold outside, the last thing you want to find is cold air coming out of your furnace when it’s supposed to be heating your home. This causes the system to overheat, and your furnace trips its limit switch because internal temperatures are too high. 1.Your Heater hasn’t had time to warm up. Well this happens sometimes and a few things can be the cause. If your forced-air gas furnace is blowing cold air, a number of factors could be to blame—many of which you can address on your own, without the immediate help of a service professional. We're sorry, but it looks like we don't offer service to this zip code. After you check your thermostat, it’s time to check your air filter. Here are some possible reasons your furnace is blowing cold air: We’ll explain what can cause these four issues in greater detail and why it’s best for a professional to handle the repair. Ensure that your thermostat is set higher than the temperature in your home. Cold air trapped inside will need to be expelled before the hot air can take its place! So 85-92°F feels cold to new heat pump owners. Pilotless ignition furnaces use a flame sensor to keep the furnace burning once it starts. Terms and Conditions | Privacy Policy | Sitemap Another noise is when you hear the furnace blower running excessively. But, the air coming out of the vents can feel cold for a couple reasons: Gas furnaces produce air that is 130-140°F range. 13 reasons your furnace is blowing cold air 1. The problem may be the thermostat fan setting. Below are some reasons you may be getting a blast of chilly air and how you can warm up your house as soon 1as possible. So when the furnace isn’t heating that air, it will come out the vents as lukewarm or cold. People get confused, and sometimes even scared when this happens. Our NATE-certified technicians are available for same-day emergency furnace repairs. When the furnace overheats, the heat exchanger becomes abnormally hot. Inadequate gas supply. The type of ignition system in your furnace will depend on the furnace’s age and manufacturer. Or the gas line isn’t supplying enough gas to your furnace. New furnaces are equipped with a spark ignitor or electronic ignition, which may require a technician to repair. Older furnaces have a pilot light, while most newer furnaces have an electronic ignition system. Ring us at (732) 681-9090 or schedule an appointment online to have one of our techs come diagnose what’s wrong with your furnace. 5 reasons why your furnace might start bowing cold air 1. Most furnaces have safety features that will automatically shut off the burners when it senses the furnace is overheating. Reason #3: Overheated furnace. Basically, the furnace isn’t lighting the fuel, meaning it can’t heat your home, either. Is the furnace’s blower constantly running? If so, this is a sign that your furnace may need to be replaced. Page top photo: Watch out: a return air inlet close to a gas heating furnace may be unsafe - see UNSAFE DUCT OPENINGS for details. Double-check that your thermostat is set to HEAT and not COOL. Do you have thermostat wars going on in your office? You may also see an error message on your thermostat, or a blinking LED light on the furnace control board. Again using Occam’s Razor, we can assume that the next likely culprit for your heater blowing cold air is your thermostat. A professional can check the limit switch to make sure it’s working correctly. Do this: Try relighting the pilot light following these steps: Step 1: Turn off your furnace After making sure your thermostat is set to HEAT, make sure the fan is set to AUTO and not ON. If your furnace is blowing cold air, give us a call today! Michael & Son Services (Corporate Headquarters) Alexandria, VA 22312 Map | (800) 948-6453, © Michael & Son Services Inc. 2003–2021. Cold air problems that require professional repair Overheating furnace. Why is my new high efficiency furnace blowing cold air sometimes? If your furnace overheats, it could end up blowing cold air. However, the fan will keep running, cooling the furnace to protect it from potential damage. Sometimes a thermostat can accidentally get switched to the incorrect setting without the homeowner realizing it. Furnaces can overheat for a variety of reasons, including: If you’ve already checked your air filter and you know it’s not the source of the problem, you’ll need to contact a professional for a furnace inspection.. If this is the case, we may have solved your problem. Called a “dual-fuel system”, the gas furnace kicks on when the heat pump can no longer efficiently pull heat from the cold air outside. When set to ON, your furnace will deliver air 24/7, even in between heating cycles. The hot and cold air pattern might happen for an extended period, and still, your house remains cold. Click here for a guide on how to fix this problem. Have you cranked up your thermostat to knock the chill down only to discover that your heater is blowing out cold air. Your furnace is supposed to heat your home, so the last thing you’d expect is to feel cold air coming from your home’s air registers when your system is running. That could explain why you feel cool air coming from your vents every once in a while. If you have a gas furnace, a lack of fuel will cause the pilot light to go out. So if you’re experiencing furnace issues, give us a call. It’s important to have a professional do cleaning and maintenance on your furnace annually, to ensure that the problems you may come to face are minimal. If... Condensate clog. 7. Incorrect thermostat setting. But as it turns out, this is a furnace problem that comes up often in many Bay Area homes. Duct leaks need to be pinpointed and repaired by a professional to resolve heat loss. Ask Question Asked 6 years, 5 months ago. When air blows over the coils, the air picks up that heat. Turn your thermostat from HEAT to OFF. A dirty air filter is a common culprit of furnaces blowing cold air. Your body temperature is around 98.6°F (everyone’s body temperature is slightly different, but that’s the average). 415-821-0560 | To help cool the heat exchanger down, the blower motor will continue to run, which will eventually cause the furnace to blow cold air for a short amount of time. Your furnace is overheating if it blows hot air, then cold air, and turns off. Check The Thermostat. If you have any questions about why your furnace is blowing cold air, or if you’d like a heating system serviced or installed in your home, contact Cabrillo, your Bay Area plumbing, heating and air conditioning contractor. If your air filter is dirty, replace it ASAP. If so, someone may have been too... 2. Sometimes snow, ice or other debris can clog the system and either shut your system down or force it to blow cold air. Make sure the thermostat’s screen is on and the buttons are responsive. A heat exchanger is a group of metal coils that are heated. This type of heating is highly inefficient. A furnace that isn’t getting fuel will not ignite and will blow only cold air. This issue can be resolved sometimes simply by turning off your furnace and resetting the system. 78 Dorman Ave San Francisco, CA 94124 United States Other thermostat issues. Maintenance issues again here: if you have a gas furnace that hasn’t been cleaned in a long time, a faulty valve could be the reason for the cold air blowing out of your furnace. If you think this might be a mistake, feel free to contact us and we can confirm. This time of year, especially when it gets cold outside in the evenings, we get many calls from homeowners concerned that there is cold air blowing out of the duct registers in their home when their heat is running. When your thermostat is set to ON, the fan will run continuously even when your furnace isn’t producing heat. Viewed 3k times 0. Your Furnace Air Filter is Dirty In such cases, a safety control device known as the limit switch will shut off the burners. Maybe the sensor that turns the fan off is not working and allows the fan to continue blowing too long. Your furnace actually heats air via a part of the furnace called the heat exchanger. Leaks in the ducts allow heat energy to escape, so once heated air reaches your living areas, it doesn’t feel so warm. Or, the valve could simply be worn out. Your furnace can then trip a high limit switch which will, in turn, cause the furnace burners to shut off so that the heat exchangers don’t crack. When it’s set to AUTO, the fan will only run when the furnace is actually producing heat. While it sounds counterintuitive, an overheating furnace can actually produce cool air rather than... A faulty ignition system. Without combustion, you won’t have heat. Your furnace’s fan is controlled by a limit switch which tells it when to turn on and off. Active 2 years, 7 months ago. Otherwise your electric heater or gas furnace will not turn on. A dirty air filter can block airflow over your furnace’s heat exchanger, which can cause it to overheat. How have you & your family been feeling? If you have leaks or holes in your air ducts, warm air can easily escape which could explain why you’re feeling cool air coming from your furnace instead of heat. Two thermostat issues that could cause your furnace to blow cold air include: Your thermostat is still set to COOL not HEAT Your thermostat fan setting is set to ON not AUTO If your furnace seems to be blowing cold air, it could be a problem with the ignition system. By switching the thermostat to “auto,” the fan will only blow when the furnace is heating the air. Dirt and debris can collect on the valve, causing it to shut down. Sometimes, a furnace blows cold air due to duct leaks. You might be able to tell if your ducts have a leak, but fixing them is another issue. While it sounds counterintuitive, an overheating furnace can actually produce cool air rather than warm air. If the flame sensor is dirty, your furnace will turn on and begin heating but then turn cold … Gas furnace. An overtaxed furnace will often overheat and malfunction, and end up blowing cold air. When you turn on a faucet to receive hot water, you often have to wait a bit... 2. Once again, the low battery voltage can be the issue here, so the best thing to do is to replace the battery. After all, a furnace shouldn’t be blowing cold air, right? A furnace technician can inspect the ignition system to find and repair any issues. Unfortunately, this is not a problem you can fix on your own. Your thermostat’s fan setting. Sometimes, the heat exchanger can get too hot and overheat. Does your furnace blow hot air sometimes and cold air other times? To troubleshoot a misbehaving gas furnace, start with the easiest explanations and solutions, then work your way to the most complicated. If they’re not, try changing the batteries. Your gas supply could be turned off. For Furnace … This is another reason to have your system checked regularly. It’s Just Been Switched On – Any furnace will blow cold air when it starts up, since it takes time for hot air to travel through the system and into your home. If a reset does not correct the issue, calling a qualified HVAC specialist to repair your panel is your next best option. 5740 General Washington Dr Furnace blows cold air: This article describes what to check if the warm air heating blower fan delivers intermittent cold air into the occupied space, or if the furnace cycles between blowing warm air & cool or even cold air into the building.. This can be caused by something as simple as a strong draft. Leaky air ducts can also make your furnace work harder as it strives to meet your desired temperature that’s set on your thermostat. Today we’re going to talk about five reasons why your furnace might start blowing cold air in your home so that you can properly take care of the issue if it happens to you! 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