A dirty air filter will restrict airflow to your furnace and can cause it to overheat. You may also see an error message on your thermostat, or a blinking LED light on the furnace control board. Here are 6 common reasons for a furnace blowing cold air, and what you should do about it: 1. Design and Marketing by LeadsNearby. This issue can be resolved sometimes simply by turning off your furnace and resetting the system. Our NATE-certified technicians are available for same-day emergency furnace repairs. The Flame Sensor is Dirty. Without combustion, you won’t have heat. 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.. A weak power source won’t trigger the sail switch, and it won’t regulate the air flow. Cold air trapped inside will need to be expelled before the hot air can take its place! 5 reasons why your furnace might start bowing cold air 1. Have you cranked up your thermostat to knock the chill down only to discover that your heater is blowing out cold air. 78 Dorman Ave San Francisco, CA 94124 United States If your furnace is blowing cold air, or is not operating at all, a component called the fan limit switch may have malfunctioned. Electric resistance heating, which use heat strips (standard with every heat pump) installed in your ductwork. After making sure your thermostat is set to HEAT, make sure the fan is set to AUTO and not ON. A dirty furnace filter is the root cause of many problems. Alexandria, VA 22312 Map | (800) 948-6453, © Michael & Son Services Inc. 2003–2021. A professional can check the limit switch to make sure it’s working correctly. 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. Why is my new high efficiency furnace blowing cold air sometimes? 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. In most cases, it’s best to have a professional identify the problem and repair your furnace. The type of ignition system in your furnace will depend on the furnace’s age and manufacturer. The hot and cold air pattern might happen for an extended period, and still, your house remains cold. Schedule service Troubleshooting tip #1: Check the thermostat If your furnace blows hot air sometimes and cool air at other times, … After you check your thermostat, it’s time to check your air filter. Incorrect thermostat setting. Turn your thermostat from HEAT to OFF. If your air filter is dirty, replace it ASAP. Make sure the thermostat’s screen is on and the buttons are responsive. Dirt and debris can collect on the valve, causing it to shut down. But first, we’ll share a couple of fixes you can try at home before you call a pro. Sometimes snow, ice or other debris can clog the system and either shut your system down or force it to blow cold air. When the filter is clogged, the furnace has to work overtime to distribute adequate amounts of warm air throughout your house. Check The Thermostat. If so, this is a sign that your furnace may need to be replaced. In such cases, a safety control device known as the limit switch will shut off the burners. Pilotless ignition furnaces use a flame sensor to keep the furnace burning once it starts. 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. If your furnace seems to be blowing cold air, it could be a problem with the ignition system. If your heater is blowing cold air, and it’s not one of the first two possible explanations on this list, then you’ll need a specialist to at least come and take a look. Your furnace actually heats air via a part of the furnace called the heat exchanger. Inadequate gas supply. If a reset does not correct the issue, calling a qualified HVAC specialist to repair your panel is your next best option. Otherwise your electric heater or gas furnace will not turn on. Ask Question Asked 6 years, 5 months ago. Or the gas line isn’t supplying enough gas to your furnace. Active 2 years, 7 months ago. 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. Cabrillo Plumbing, Heating and Cooling ©document.write(new Date().getFullYear()) | All Rights Reserved | Viewed 3k times 0. Duct leaks need to be pinpointed and repaired by a professional to resolve heat loss. Double-check that your thermostat is set to HEAT and not COOL. 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. If it’s not, they can replace it. With electronic ignition systems, cold air could be caused by an electrical issue or if parts need to be adjusted or replaced. If they’re not, try changing the batteries. Cold air problems that require professional repair Overheating furnace. Michael & Son Services (Corporate Headquarters) If your furnace overheats, it could end up blowing cold air. When your thermostat is set to ON, the fan will run continuously even when your furnace isn’t producing heat. When the furnace overheats, the heat exchanger becomes abnormally hot. If you have an older furnace and your pilot light is unable to stay lit, the ignitor won’t light the burner and there will be no combustion. Reason #3: Overheated furnace. 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. 1 When the thermostat stops calling for heat, the furnace will turn the electric heating coils off, but allow the fan to continue blowing air until the coils cool down. Do this: Try relighting the pilot light following these steps: Step 1: Turn off your furnace That could explain why you feel cool air coming from your vents every once in a while. When set to ON, your furnace will deliver air 24/7, even in between heating cycles. For Furnace … When it’s operating properly, the switch will turn on after the burners have completely warmed up the air and blown it across the heat exchanger, so only warm air is being blown into your home. 1) Thermostat is set to ON Is your furnace blowing cold air only sometimes? The type of ignition system in your furnace will depend on the furnace’s age and manufacturer. When your heat pump sometimes blows cold air even when the setting for heat is on, it’s an alarming problem and depending on the cause, a common enough one. The problem may be the thermostat fan setting. 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. New furnaces are equipped with a spark ignitor or electronic ignition, which may require a technician to repair. 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. Basically, the furnace isn’t lighting the fuel, meaning it can’t heat your home, either. All Rights Reserved. Again using Occam’s Razor, we can assume that the next likely culprit for your heater blowing cold air is your thermostat. If the flame sensor is dirty, your furnace will turn on and begin heating but then turn cold … Leaky air ducts can also make your furnace work harder as it strives to meet your desired temperature that’s set on your thermostat. 13 reasons your furnace is blowing cold air 1. This field is for validation purposes and should be left unchanged. It’s the beginning of a heating cycle. When it’s set to AUTO, the fan will only run when the furnace is actually producing heat. We're sorry, but it looks like we don't offer service to this zip code. Thermostat: A Furnace Blowing Cold Air Could be Due to Your Thermostat. Your furnace’s fan is controlled by a limit switch which tells it when to turn on and off. Page top photo: Watch out: a return air inlet close to a gas heating furnace may be unsafe - see UNSAFE DUCT OPENINGS for details. Maybe the sensor that turns the fan off is not working and allows the fan to continue blowing too long. Do you have thermostat wars going on in your office? By switching the thermostat to “auto,” the fan will only blow when the furnace is heating the air. 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! This is another reason to have your system checked regularly. Your thermostat’s fan setting. Your furnace is overheating if it blows hot air, then cold air, and turns off. Unfortunately, this is not a problem you can fix on your own. A furnace that isn’t getting fuel will not ignite and will blow only cold air. A dirty air filter is a common culprit of furnaces blowing cold air. Possible Conclusion 1: It’s … This type of heating is highly inefficient. 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. There are two possible routes here, one of which many homeowners who are new to heat pump systems encounter. Clogged air filters could be causing cold air to blow out of your vents. While it sounds counterintuitive, an overheating furnace can actually produce cool air rather than... A faulty ignition system. So when the furnace isn’t heating that air, it will come out the vents as lukewarm or cold. A dirty air filter can block airflow over your furnace’s heat exchanger, which can cause it to overheat. But as it turns out, this is a furnace problem that comes up often in many Bay Area homes. When air blows over the coils, the air picks up that heat. To troubleshoot a misbehaving gas furnace, start with the easiest explanations and solutions, then work your way to the most complicated. Gas furnace. Is the furnace’s blower constantly running? Well this happens sometimes and a few things can be the cause. One of the most common causes of a furnace blowing cold air is not actually a repair at all. When the weather turns especially cold—as has been the case this year in Sacramento and much of Northern California—we often get calls from customers reporting that their heat pump-powered heating systems are blowing cold air through the vents, no matter how high they turn the thermostat. A furnace technician can inspect the ignition system to find and repair any issues. Other thermostat issues. Does your furnace blow hot air sometimes and cold air other times? 1.Your Heater hasn’t had time to warm up. Your gas supply could be turned off. Call a professional so they can do an inspection and identify and repair any leaks. Click here for a guide on how to fix this problem. This causes the system to overheat, and your furnace trips its limit switch because internal temperatures are too high. When you turn on a faucet to receive hot water, you often have to wait a bit... 2. Sometimes, the heat exchanger can get too hot and overheat. While it sounds counterintuitive, an overheating furnace can actually produce cool air rather than warm air. 5740 General Washington Dr Once again, the low battery voltage can be the issue here, so the best thing to do is to replace the battery. 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. Your body temperature is around 98.6°F (everyone’s body temperature is slightly different, but that’s the average). 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. So Why Is My Furnace Blowing Cold Air Instead Of Heat? If neither your thermostat or your air filter seems to be the issue, there may be a bigger problem at hand. Sometimes a thermostat can accidentally get switched to the incorrect setting without the homeowner realizing it. When the air filter is dirty, airflow through the system is restricted and the furnace may not be heating the air. 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 is blowing cold air, give us a call today! How have you & your family been feeling? So 85-92°F feels cold to new heat pump owners. Your Furnace Air Filter is Dirty 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. Privacy Policy. Another noise is when you hear the furnace blower running excessively. People get confused, and sometimes even scared when this happens. If this is the case, we may have solved your problem. If so, someone may have been too... 2. 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. 415-821-0560 | If the thermostat isn’t responsive, call a professional. You might be able to tell if your ducts have a leak, but fixing them is another issue. If the limit switch is broken or not operating properly, the fan can turn on too soon, which can cause cool air to blow out of your vents. A heat exchanger is a group of metal coils that are heated. 7. 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. Older furnaces have a pilot light, while most newer furnaces have an electronic ignition system. Sometimes, a furnace blows cold air due to duct leaks. Does your blower turn on & off frequently or does it blow cold air sometimes? 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. New high efficiency furnaces have what is known as a condensate … Bay Area plumbing, heating and air conditioning contractor. If your furnace starts to run properly after the filter is changed, you’ve solved the problem. This can be caused by something as simple as a strong draft. VA Master Plumber/Gas Fitter #2710019013 • VA Class A Contractor #2701038423 • MD Master Plumber/Gas Fitter #82253 • MD Home Improvement #123872 • MD Master Electrical #3952 • MD Master HVAC #65489 • DC General Contractor #420211002808 • DC Master Electrical #EM900824 • DC Master HVAC #RC 901906 • DC Master Plumber/Gas Fitter #PGM10542 • WSSC Master Plumber/Gas Fitter #PFG 73421. Leaks in the ducts allow heat energy to escape, so once heated air reaches your living areas, it doesn’t feel so warm. An overtaxed furnace will often overheat and malfunction, and end up blowing cold air. If... Condensate clog. However, the fan will keep running, cooling the furnace to protect it from potential damage. 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. So if you’re experiencing furnace issues, give us a call. If you think this might be a mistake, feel free to contact us and we can confirm. Ensure that your thermostat is set higher than the temperature in your home. After all, a furnace shouldn’t be blowing cold air, right? Another reason your furnace might blow cold air is if the electronic control panel is broken. 2. Terms and Conditions | Privacy Policy | Sitemap Most furnaces have safety features that will automatically shut off the burners when it senses the furnace is overheating. Blowing Cold Air. If you have a gas furnace, a lack of fuel will cause the pilot light to go out. 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.. Or, the valve could simply be worn out. Problem and repair your furnace might blow cold air filter seems to expelled... They ’ re not, try changing the batteries that could explain why you cool! Heating cycles heat and not on electronic ignition systems, cold air, cold. Asked 6 years, 5 months ago discover that your heater blowing cold air it. The burners after making sure your thermostat is set to heat, make sure it ’ s beginning. 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