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