While there could be different reasons for your Nest thermostat not cooling and blowing hot air on cool mode, this guide provides the most common ones. If the filters are dirty, you can wash them or replace them. Replace single-pane windows with more efficient double-pane windows. For instance, some Daikin models have a blinking light on the indoor air handler that only lights up when aux heat is ON. Home maintenance needs change in the winter. - edited First of all, this happens when you don't wire it according to the heat pump row. Is it working? Its important to perform regular maintenance checks to ensure your heat pump is working properly, especially as the colder months roll in. As weve mentioned, auxiliary heating is a separate mechanism from the heat pump. Choose between Max Savings and Off. To make sure we provide the most qualified technician, please share more about your needs. If you dont have a wire in the W2/AUX connector, you dont have AUX heat. If it remains on, you may have a malfunction in your heat pump and need to call an HVAC service provider. The O/B is just reversed and can be fixed by setting it correctly. Should you have any new issues, updates or just a discussion topic, feel free to start a new thread in the community. If you think that the wires are configured incorrectly, contact a. Thermostat shows auxiliary heat and blows cold air You can pull the cover off the tstat if you have a w2 and e terminal. Your thermostat is probably blowing the hot air because you use conventional heating (furnace). . This means that with the exception of unfortunate, unforeseen external interference, you can avoid using AUX heat to hit the target temperature all winter long. Here is a option to validate the issue. If you have a gas furnace the fuel type should be set to gas, which will delay start of the blower until the furnace warms up. To understand what could go wrong with your auxiliary heat function, its important first to understand how aux heat works. Thanks! Seal air leaks around fireplaces, chimneys, furnaces, and water heaters with fire-resistant materials like sheet metal, sheetrock, or furnace cement caulk. To check whether the problem is with the Nest orientation settings or not do the following, 1)Put the thermostat on heat and raise the temperature a bit higher than the current room temperature. Reddit and its partners use cookies and similar technologies to provide you with a better experience. Important: Do not touch the wires in your thermostat while you check them. Note: Use the Home app if you have a Nest Thermostat. You are correct! See if your unit is blocked by snow, ice, or fallen shrubbery. I did a factory reset of the thermostat.2. Auxiliary heating is dependent on a couple of factors, one of them being that indoor temperatures must be higher than a specific setting usually 40F. They transfer the warmth or coolness from one place to another. If the problem doesnt go away after trying out these tips, perhaps call in local HVAC experts for help. Airflow in the ducts can be compromised for several reasons. The option is greyed out. For a 1st stage heat pump, these are the terminals that are supposed to be connected. How much do you know about it? Youll know that you have a heat pump by putting your thermostat on heat mode and if your outdoor unit kicks on. Your air filter may also need to be cleaned or changed if it is clogged and unable to efficiently let air through. Test your heating and cooling again to make sure the issue is resolved. Nest thermostat blowing cold air in heat mode. Your system can use AUX heat to help keep you comfortable in harsh weather or to help change the temperature in your home quickly. No matter which setting you choose, Heat Pump Balancedetermines how often expensive AUXheat is used. Check Your Settings This is step #3 of the "Captain Obvious" portion of your troubleshooter. Therefore, the heat pump may no longer supply enough heat inside the house. I have also tried removing the Nest and re-installing the original thermostat and confirmed that the heat does still work with the old thermostat. As most of the posts out there when my thermostat is set to blow hot air but it blows cold air. Your Nest thermostat is not compatible with your cooling system. The same may happen if indoor temperatures are higher than the thermostat setting, but outdoor sensors call for aux heating. : The first thing you should do here is to check your thermostat. How old is your system? Find the model number of your system, either in the user manual or on the sticker label of the outdoor unit and look it up on the internet. Here are some wiring diagrams for heat pumps that could help you. Additionally, check any other signs on the heat pump designed to alert you when the heat pump is on. If your nest thermostat not cooling to set temperature, you should cross-check the wiring. You need to be aware of what type of system you have and the type wiring that suits. New install of Nest Learning Thermostat and we are getting cold air blowing. Lets find out. Finally, bends can also constrict the ductwork, limiting the amount of warm air that passes through. Auxiliary heat should be a temporary setting and automatically turn off once your home warms up. Thankfully, this is an easy fix. Most such systems are wired to a gas furnace. Only turn your heat up two degrees at a time. Proper and regular maintenance is vital because it helps you catch and address potential issues early. If this terminal is loosely connected or not connected, it will cause problems with your thermostat controlling heating and cooling for your heat pump. Maybe youve even conformed on the thermostat that its ON. I've also written out the connections on the old thermostat as the labels are hard to read behind the wiring. Aux heat isn't ON. On nest learning thermostat and thermostat e, under thermostat go to settings then select equipment and continue. A changeover valve can become defective with the age of your system. 90% of all HP systems use O to energize in cooling not heating. Scheduled professional checkup, at least once per heating season, is especially crucial. It means that the auxiliary heater can malfunction without necessarily affecting the heat pump. (~50s), but as it got colder (30s), the condenser has stopped trying to spin up. Youll stay warm, but emergency heat mode will cause a noticeable spike in your electricity bill. Whenever youre using AUX heat instead of your heat pump you risk running up the electricity bill a lot. Did you ever get it figured out? Changing this setting will also depend on the type of thermostat you have. This type of heating is often triggered when the outdoor temperature drops to near or below-freezing temperatures. Otherwise, if the problem hasnt been resolved, its perhaps a good idea to call in professionals. What Is the Newest Nest Thermostat Out Now? Ensure also that the end of the wire connecting to the O/B terminal is stripped enough to have proper contact with the terminal. Manage Settings Amazon and the Amazon logo are trademarks of Amazon.com, Inc or its affiliates. Use the G wire for the fan. Hi, I am troubleshooting a nest thermostat that is blowing cool/cold air when it's supposed to be heating. I've tried switching the heat pump from B to O. I have no experince in HVAC but I believe I have1 Stage Heat Pump with Aux heat and Emergency Heat. Your System Is Not Compatible with Your Nest Thermostat, Nest Thermostat Not Turning on AC Compressor [Solved], Google Nest Learning Thermostat Programmable Smart Thermostat for Home 3rd Generation Nest Thermostat Works with Alexa White, Google Nest Thermostat Smart Thermostat for Home Programmable Wifi Thermostat Snow, New Honeywell Thermostat Blowing Hot Air on Cool [Solved], What Size Mini-Split Do I Need? Nest thermostat blowing cold air on heat. Also, if you happen to have a voltmeter, then you could test whether the Nest is signaling Aux heat by testing the voltage of the white wire (and blue) at the heat pump. This is a perfect troubleshooting guide for you if you are dealing with a Nest thermostat that is not cooling and blowing hot air on cool mode. Make sure your heat pump is receiving power and check that your thermostat is set to heat. This device is designed to measure the temperature of the air flowing out of the vents in your home. Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type. Auxiliary heat is a secondary heating function your thermostat automatically switches to when its too cold outside for your heat pump to extract warmth from the air. After installing the Nest, during the heat pump test, my system blows warm air just fine. If it is than you either have one of tow issues. On the orientation configurations, if O is one that is highlighted, try changing it to B and vice versa. Or perhaps the thermostat battery is depleted. 11:35 AM. When your heat pump goes into defrost mode, it switches into cooling mode, causing the outdoor coils to heat up to melt any frost or ice within the system. Privacy Policy. YourNest thermostat willadjust your lockout temperature based on how your heatpump is working. If I try to move the black cable to W1 then it thinks that its gas and not electric. The orientation settings on your nest thermostat switches between the heating and the cooling mode. Sometimes systems may need the C-wire to be installed to be compatible. For example, if your AUX lockout temp is 40F or 4.4C, then AUXheat will come on when the outdoor temperature is below 40F or 4.4C. You can set a lockout temperature manually in the Equipment menu of your thermostat. Model GMS80704BXCC. However, because the system is in cooling mode . If thats the case, you may need to recheck the thermostat wiring. Ensure where your plumbing, ducting, and electrical wiring comes through the walls, floors, and ceilings is properly sealed. Now you know theres no need for immediate panic. Scan this QR code to download the app now. Under the thermostat, tap the settings icon on the top right (looks like a gear). A heat pump is equipped with a reversing valve. This can help prevent false alarms in the future. Auxiliary heat is a heating mechanism designed to fill the gap to keep you warm and cozy even when the heat pumps heating capacity diminishes. The heat pump is your homes primary heating source, but when the weather gets too cold, a secondary heating source is needed. Tell us more and well help you get there. Check your thermostat settings and clean your air filter. Its not changing from cold to hot. Were you able to try Patrick's suggestion above? Bring up your Nest app. Currently, AH runs, blowing cold air while thermostat says heating. Remember that the display on the thermostat an LED system that can malfunction. You dont have to connect your Nest thermostat to your Wi-Fi network. To use Heat Pump Balance, your thermostat must also be connected to Wi-Fi. I cant change the Heat Fuel Source. marcusmoreno23, I'm dropping by to check if how's your Nest Learning Thermostat now? If your unit and filter are free of debris, the problem could be low refrigerant levels. If its higher than 40F, you dont need heating, and the aux ON display was probably a false alarm. When it gets extremely cold outside, the thermostat automatically switches on the resistance coils, which function just like any electric heater. 1. I've tried switching the heat pump from B to O. Although its not common, its also not unusual for auxiliary heat to misbehave or fail. If the O option is highlighted, select B. A technician will be able to get this problem sorted out in no time. On your outdoor condenser unit, look for the systems specification label and check if there is anywhere written heat pump.