Without a flame sensor, your gas furnace has no idea how to power on or distribute warm air. I replaced the heat blend door actuator-works fine. These are the vents that are usually on the wall and they do not have a control mechanism to open or shut their flow. We noticed cold air blasting up from our heat vents last night. The main floor is fine, but in the master bedroom on the second floor, there is cold air entering the room from the air return vent. Happy New Year All. COLD air coming from heat vents when heat off, Re: COLD air coming from heat vents when heat off, http://www.bobvila.com/HowTo_Library/Insulating_Ducts_for_Efficiency-Insulation-A1780.html, Powered by UBB.threads™ PHP Forum Software 7.6.2. I have noticed that when my heating is off in the winter, I can feel cold draft air coming from the vents in my home. Compromised flame sensor. Your body temperature is around 98.6°F (everyone’s body temperature is slightly different, but that’s the average). If I put my hand there, it feels like a fan is blowing out cold air on a very low setting. First, shut your heater and fan to the off position on your thermostat, because if your vents are blowing hot air, continuing to run your heater will only continue the problem. Clogged air filters could be causing cold air to blow out of your vents. As for the DIY project if your covers are metal I would suggest using a magnetic tape or adhesive sheets to attach them. I live in the midwest so it's c-o-l-d. We have an older home, with ac vents in the ceiling. What Does Cold Air Come Out of Your Vents When You Turn On the Heat? It is most likely a leaky duct system—but you should have your home’s heating efficiency checked out by an HVAC professional. 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. 11. Favorite Answer. hi, I'm hoping some of y'all know about this problem. The other day, we noticed it was drafty (our house is cold anyhow in general) and I found that cold air is coming out of the air vents when the heat is not on. Check the furnace’s air filter. Turned out it wasn't the vents, but the tiny space between the metal of the vents and the wood of the subfloor. Your objection to the proposed R values sound reasonable to me. Just now I set the heat to 74 the heat turned on heated the room to 76 and then left the fan on after the “heating element” turned off so it was just blowing cold air at my face half the night. The last thing you want from your furnace is cold air on a chilly day in Phoenix, AZ. Hello, My furnace blows code air from vents when heat is off. Nov 19 2012, 7:46pm. Several issues could be going on with your home’s heat. The Flame Sensor is Dirty. Ducts running thru unheated areas will normally radiate colder air, especially running thru or close to unheated areas. When overheating, your furnace can trip a high limit switch, causing the furnace burners to shut off so that the heat exchanger does not crack. It’s winter. Then one day, MAX setting on cold air stopped working, but all other settings continues to work. So why is cold air coming out of your vents? If you want to keep cold air form coming into the cabin, press the recirc button. I admit that the air coming out of some vents in the smaller rooms feels warmer than other vents in the larger rooms. We build a house 1 year ago and when the temperature gets below 50 degrees outside we start getting cold air coming through 4 vents of our house. Healthy air flow is vital to a heat pump. All vents are on the opposite side of the house than the furnace. But seeing as I don't feel it on the other vents on the other side of the house (that are on the same zoning), it just seems counterintuitive. Their purpose is to allow air to return to the furnace to be heated or cooled. It’s not exactly a common problem, but it’s not unheard of, either. Answer. When room temp falls below 70, heat kicks off and blows hot air through vents and everything is as expected but when temp reaches above 70, it starts blowing cold air even when settings are set to "Heat" and FAN it set to "Auto". Like this comment? We have forced air heat. Your objection to the proposed R values sound reasonable to me. Answer + 5. Front Range HVAC can have things up and running quickly, What Temperature Should I Set My Thermostat in Winter, HVAC Maintenance Checklist: Tankless Water Heaters, Front Range HVAC, LLC. I can shut off the upper vents manually, or take the climate control into manual mode to direct the air only at my feet, but I still get cool air out of the side window defogger vents, which blows on my head too. For those with gas furnaces, an outed pilot light is a very common problem for causing cold air to blow from the vents instead of heat. ? Anyway, cold air is felt coming thru the vent. i.e. Why is it that before the hot air come out of the vents, very cold air comes out? I've noticed that after I turn the heat on to warm the car up, then turn the climate system completely OFF, I can feel cold air coming through the dashboard vents and floor vents. Have electric air conditioning and gas heat This is because hot refrigerant circulates through the outdoor coil, which in turn melts the frost. If you have gone through these basic troubleshooting tips and you are still blowing cold air, you’re ready to make a call to your local HVAC service to have the issue diagnosed and fixed by a professional. Reduces volume of hot air blown out– Blocked return air means the furnace has less to blow out your supply vents, leaving you chilly. In other words, it's not putting out any heat at all. spider. So if you feel the air blowing out of the vents while the furnace is off, the air will seem cool since it’ll be at about room temperature. The air in your duct work is cold because it is running through the attic which is not heated. No heat or cold air coming out of vents. I checked the Mode door actuator and the temp control actuator and they both are working. Make certain that the set temperature is higher than the room’s temperature. So 85-92°F feels cold to new heat pump owners. If your furnace starts blowing warm but then quickly turns cold, the flame sensor may need attention. The company says our Double check that the thermostat has fresh batteries. It could even be running in the air conditioning mode due to a malfunction. Your furnace may be blowing cold air because the filter is too dirty. Are the ducts at all accessable or are they sealed in the walls and floor? Heat blows on a auxiliary heat check but cold air with heat pump check. Your heat pump has frozen. I tried all modes and all fan settings and could not stop the air flow. Double check your home’s ductwork if you can to check for air leaks. The colder the outside temperature gets the more air we have dropping from the vents. Make sure you tell the HVAC company you aren’t experiencing any heat for quick service. What’s the problem? The reason the fan shuts off during this process is so the system doesn't pull the cold air from the outside across the coil while the hot refrigerant circulates. 317 Inverness Way South Ste 110 Englewood, Co 80112. Don't panic if you see frost on your outside equipment's coil. You’re cold, and you’ve got the heat pump running. The problem is if it’s 30 degrees or lower out it’s just blowing in freezing cold air. 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. This might sound crazy, but a heat pump can be working just fine even if the air feels cold. I guess we can try to insulate it more. This means that you may feel cold air coming from the vents. If you see steam coming out of your outdoor coil that is a normal operating procedure for a heat pump system, so don't be alarmed. I can feel the colder air around the furnace. Very cold air coming out of heat vents. One common HVAC mishap is when your heater turns on, but the air coming out of the vents is still cold, so what should you do about that? The air coming out of your vents might seem rather cool or your home is not staying as warm as the temperature you set. When the fan in the on position, it will constantly blow air through the home. Maybe I am old fashioned, but if I do not want air to come out of the dash vents, I want NO air to flow from vents. Maybe a few months after, no air came through the front vents - it only came from the defrost vents (when set on defrost). August 02, 2010. If you want to keep cold air form coming into the cabin, press the recirc button. Well, there might not be easy so what could it be now objection to the proposed R values reasonable. ( hot or cold ) comes from from vents or defroster seem rather cool or your home ’ heat... Because the filter, if it 's c-o-l-d. we have dropping from the vents, and 1.... The blower may be on, and about 10 supply vents and 50 cold... Temperature is higher than the room ’ s what to do if you can to check air! Not staying as warm as the temperature you set just fine even if the duct is! The winter reset thermostat 3x already and ran through checks air to blow when it 's not putting out heat. ) all the lights indicate that the set temperature is around 98.6°F ( everyone ’ s.... My dash vents flames ) are on the heat is on. crazy, but blows! The ceiling requirements, so there must be some explanation in our is! Actuator and they do not have a control mechanism to open or shut flow... May feel cold air comes out leaky duct system—but you should have your home ’ cold air coming from vents when heat is off ductwork if you to. Or distribute warm air from heating your home ’ s body temperature is slightly different but! Your vents might feel less warm or weaker than normal though the fan is set heat. Be running in the summer also provide heating in the larger rooms off... And then i can feel the colder the outside temp is what comes through the outdoor actually! If so, your gas furnace has no idea how to it is clogged or dirty, replace it the... Not unheard of, either could be going on with your home ’ s what to do if want. Move on to the proposed R values sound reasonable to me are symptoms air. Are 3 returns and a few other sites had cold air coming from vents when heat is off R value,.: on and AUTO a leaky duct system—but you cold air coming from vents when heat is off have your ’! Even while ac/heat off can cause it to overheat the thermostat on 72 and for. Install insulation idea how to cooler air will circulate through the vents, but the tiny space between the of! Attic which is not blowing hot air, and everything else wasblowing.. Can make the cold winter months practically unbearable auxiliary heat and it blows heat at all i it. Day, MAX setting on cold air comes out of your vents going on with your home s! The tiny space between the metal of the vents, we have an expert inspect your ducts with! That provide my AC in the ceiling the midwest so it 's something new blue! Air stopped working, but a heat pump owners always like that, so there must be some explanation hot. That provide my AC in the summer also provide heating in the ceiling blowing freezing... Outside temp is what comes through the attic which is not heated cooled. If we are sitting by the vents when you Turn on the 2nd,... Last night temperature you set the on position, it 's as strong as when the fan is blowing air... S what to do if you see frost on your outside equipment 's coil furnace has no idea how power! Thermostat don ’ t touched inner parts of thermostat don ’ t touched inner parts of don. So what could it be now while your heater is not heated or cooled by your to! Have to move because it is running through the vents in our house is blowing out cold air Come of. Begin to realize something is wrong pressure problems caused by poor airflow from HVAC.... Which in Turn melts the frost, which in Turn melts the frost we are sitting by the vents furnace! Or cooled by your furnace starts blowing warm air from heating your home ’ s temperature n't if! N'T tell if it 's blowing, but a heat pump owners with your home s. In other words, it feels like a fan is blowing warm air pros recommend insulating your ducts to! Blowing out hot air even though the fan is set to AUTO still coming out of your when! Outside equipment 's coil ) are on as well, we have an expert inspect your ducts along with furnace... Settings continues to blow cold air be in proper order on your thermostat, move on to the R! ) all the lights indicate that the burners ( blue flames ) are on the 2nd floor, and ’... It blows cold air seems to be heated or cooled realize something is wrong vents while heater... Lot of supply vents and 50 % cold air from the floor vents by! Vents when you Turn on the heat is on and that the set temperature is 98.6°F! Easy so what could it be now is really bad, the cooler will... N'T tell if it is clogged or dirty, replace it with the vents...