Hi all, I think our thermostat/furnace isn't working properly. It’s not uncommon that an improperly set thermostat is to blame for your air conditioner blowing hot air. 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Contact Support at 1-855-733-5465 to find a pro-installer in your area. 15. How you’ll know this is your issue: Your furnace blows hot air but that … Contractor's Assistant: Did you double-check the thermostat's settings? Your furnace is overheating. Incorrect Thermostat Settings. Then select HVAC. Incorrect Thermostat Setting Photo by Wesley Tingey on Unsplash. Post photos, respond to polls and access other special features. Explanation: If your furnace is overheating, that means your heat exchanger is getting too hot. My truck started taking long to heat up so I had the thermostat changed and now it still only blows warm air after running for at least 30 minutes. I tried to change the battery, but even when I removed it from the wall plate, the thermostat was still showing "COOL". Check this easy fix first, ensuring the thermostat is set to cool, and the temperature optimally adjusted. How does a thermostat work? Probably just needs a new thermostat. Improper thermostat setting. They heat up air using a flame or heating coil and then a fan pushes that air through your home. The Reasons for Car Heater Blowing Cold Air. Any insight, advice, help, etc. This is why you hear the term “forced-air” associated with heaters. I then reset it and added the second white wire (s1 wire) into the o/b wire slot to see if that changes anything. When the system is not calling for cooling, the air that is circulated can feel warm coming out of the registers. My old thermostat only had 4 wires, White, Green, red and Yellow. Before calling a technician, the first thing you should do is take note of your thermostat settings. I've tried troubleshooting. Press Menu on the main screen. Gain access to our free AOP (Ask a Professional) Section to get real answers for your questions. W2, G, W, C, Y, R. There is one rogue wire that was not connected to the old/working thermostat, and can be seen in the picture of the old honeywell thermostat (it's brownish color I think). Once it’s switched, try your AC again. Heat pump not heating. At times, the air would keep running but would blow warm air..it keeps overriding the set temperatures. Old tstat had Y, RH (with jumper to RC), W, and G wires. Thermostat Issues. The air could be warm but still feel cool. A more common mistake (and the one he made!) I don't have a pic of the new one wired in, just the back of it w/out the wires--but I matched the letters, even labeled each wire as I removed it from the old thermostat. When I first installed it, it was only blowing hot air. While conventional gas or electric furnaces blow hot air, from 130 to 140 degrees for short periods of time, a heat pump will gently blow warm air, from 110 to 115 degrees and stay on longer to circulate it. Might there be a chance someone bumped the thermostat in the wrong direction? I installed a new thermostat in our new house and like i said, it's blowing air, but the air is not cold. So the old thermostat was working properly correct? However, the thermostat was showing "COOL" in the OFF state. I had a Honeywell thermostat and it stopped working so I replaced it with the same model Honeywell thermostat (it's an upgraded version- more current, but the same model essentially). Air conditioner blowing hot air after replacing the thermostat. I have a Honeywell thermostat that keeps acting weird, I have the set temperature at 78 for the whole day. Had the thermostat replaced on my 2005 1.9TDI (manual) a week ago, then 3 days ago, having driven 6+ hours, the aircon stopped blowing out hot air… If the thermostat is set to ON, the blower will run continuously throughout the day and night. Go to System. With the new Nest Thermostat installed, my A/C is only blowing cold air. The heat that comes through the vents is generated by the coolant being passed through a heater matrix (it's like a miniature radiator) behind the dashboard. Might there be a chance someone bumped the thermostat in the wrong direction? When your thermostat setting is on heat, it blows cold air when it should be blowing warm air. Here's how it was set up when it was working: Here's what Sensi said to do on the app as I installed it: It's installed exactly like the image. When a car heater not blowing hot air, the problem is likely to be with the cooling system. Update amazon now offers a free smart home consultation After two not helpful calls with Honeywell, I have the unit set on Cooling and it is blowing hot air. The instructions depend on which thermostat you have. There are many potential reason that your system may be blowing hot air. EMPTY OIL TANK. One of the reasons as to why your air conditioning system may be blowing warm air is due to the way that your thermostat is set. Q: My truck started taking long to heat up so I had the thermostat changed and now it still only blows warm air after running for at least 30 minutes. Be sure you’ve set your thermostat to Auto or On, as well as Cool. This is plenty warm to heat your home to your desired 72°F. 1 runs fine the other 2 just blow heat no AC. Installed a new thermostat and now it is blowing hot air on the air conditioning setting, yes, yes, did I mess up the - Answered by a verified HVAC Technician We use cookies to give you the best possible experience on our website. For a heat pump or heater to produce warm air, air must flow easily through the … We installed a new theromostat. Hi Guys, I've just updated all of the thermostats in my new office build. I have all the cable going to the correct color, no wire is touching another wire. 78 would go up to 85 the house would get so hot. When I sit at red lights the truck blows cool air . It may sound obvious, but the first thing you should check is the thermostat. I just keep shutting off the AC and turning it back on after 10 minutes usually this works. Follow the activation and programming instructions that came with the new thermostat. Nest Thermostat E . Also, when turning the Cool on, hot air is now coming out instead of cool. I've tried troubleshooting. If your furnace keeps blowing cold air, you may notice that your air filter is too dirty. Check to see if your thermostat is set to ON or AUTO. Take pictures of the terminal strip on the stat next time. Today, I rechecked the wiring and installed it again. Hello and thanks for reading / giving any advice that you're able to offer. Well this happens sometimes and a few things can be the cause. Improper thermostat setting. An air lock prevents the coolant from circulating properly and can cut your heat output. So, I think I had a bad thermostat. Yes... we are 20 years old. new honeywell stat blowing hot for ac I just installed a Honeywell rth2310b programmable thermostat and now it is blowing hot air instead of cold in the cool mode. Before calling a technician, the first thing you should do is take note of your thermostat settings. Here are some troubleshooting tips that could save you some money and time. If you have a gas furnace and you have cold air blowing from your furnace then you should check to see if there are any issues with your gas supply or supply lines. Sometimes people bump into the thermostat and change the setting from “cool” to … Simply flip the thermostat setting back to “cool” and see if the air conditioner begins to blow cool air … I'm not sure if it blows cool air when set to heat as the temperature here (currently 72 outdoors) doesn't allow me to get it to try and heat. While conventional gas or electric furnaces blow hot air, from 130 to 140 degrees for short periods of time, a heat pump will gently blow warm air, from 110 to 115 degrees and stay on longer to circulate it. This caused the issue I was having and was resolved by simply going back and changing that part of the set up. The Pilot Light is Out. Do you have a picture of the newly wired thermostat? Honeywell RTH6360 but it is blowing hot air even though the thermostat is set on cool. So thank you guys of the R/HVAC sub and even beyond for your hard work. Components – Coils, Heaters, Motors, etc. First, check to make sure the thermostat is set correctly. 78 would go up to 85 the house would get so hot. Participate in over 40 different forums and search/browse from nearly 3 million posts. Honeywell RTH6360 but it is blowing hot air even though the thermostat is set on cool. With the new Nest Thermostat installed, my A/C is only blowing cold air. Ask Our Pros-Owner Assistance - NO DIY advice will be given. This means that your unit may at times stop working and start blowing cold air. Dirty air filter. If you just turned on the heat, hot air may not yet be flowing through your air ducts. 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