Share: 27 replies. Sometimes, when you’re using too... 3… If you have a Honeywell thermostat not turning on the AC or the heat, this could be a quick fix. Our thermostat died yesterday, but after replacing the dead batteries with fresh batteries, and confirming the LCD screen was operable, our AC no longer turns on. If your AC unit won't turn on, the first thing you should check is if there was a blown fuse or a tripped breaker. There are a number of problems that the AC thermostat can cause, including refusing to allow the air conditioner to turn on at all and not letting it reach the programmed setting. Like any other equipment, thermostat can suffer from dust. An AC thermostat that won't work can be incredibly annoying. It can even cause a short circuit which can damage your thermostat or affect its operation. This symptom indicates when your Duo Therm Thermostat won’t stay on or won’t start at all. Dead Batteries . mothratl. If you hear or feel the AC unit kick in, it is operating correctly. Thermostat won’t add to scene as a responder. Unfortunately, the cheaper the filter, the lower the quality of materials, meaning you’ll need to change them more often. You would need to turn the breaker off to your air handling unit or furnace whichever type system you have. Before I look into the possible reasons your AC can’t keep up with the warm weather, I need to bring your attention to an important fact about the thermostat: lowering the thermostat doesn’t give you more cooling! To find out if the ON/OFF switch was triggered, look at the indoor component of your AC and check for a switch that looks similar to a light switch (this should be relatively close to the unit). Turn the dial or set the temperature switch to the lowest setting, such as 60 degrees F. Wait five minutes to see if cool air begins to flow. Most analog thermostats have one switch for indicating heat, cool, and off and a second switch for turning the fan on auto or off. If the thermostat is not functioning properly, there are a number of ways you can try to troubleshoot it yourself. An AC unit works by absorbing the hot air and moisture inside the space. Your AC works by passing air over condenser coils which remove the heat from the air. Then turn on the power and check the voltage in the thermostat supply terminals. My husband hooked up the nest thermostat to our new home. Perhaps your model of thermostat is equipped with additional fuse which protects it from power surges. We’ll also provide preventive maintenance to help avoid glitches in the future. Thanks for any help! If you hear a hissing sound coming from your air conditioner, (or if you’ve tried the other options and haven’t found the culprit to your AC not turning on), call an HVAC professional as soon as possible. If there is no voltage in the supply wires – the problem is not in the thermostat itself, but … Thermostat not working correctly: causes, solution. You would need to turn the breaker off to your air handling unit … Turn off your air conditioner, at least the cooling function. In this scenario, if you want your place to heat to 74 degrees, then with the +3 degree offset, you’ll need to turn the thermostat up to 77 degrees. Turn off your AC at the thermostat. Thermostat Issue. Then turn on the power and check the voltage in the thermostat supply terminals. Replace the dirty filter with a new one. I connected the nest thermostat and tested. AC Filter Change; Why Your AC Won't Turn On - The AC Crash Course. The Handyguys says: May 19, 2015 at 2:03 pm . You’ll find two main problems in this case. | Contact. Thermostat won't turn on heat/ac/fan. Before you call a professional because your AC won’t turn on, read these potential culprits first. The thermostat cannot diagnose issues with wiring at the furnace. We have changed the batteries in the thermostat unit, and checked the circuit breakers. You have no heat! To do this, turn the power off, remove the thermostat from the wiring box without disconnecting the wires. If you use preventative maintenance with a quality HVAC service, the likelihood that your furnace won’t work properly when you need it to goes down significantly. This is especially common in models which have a rotary type thermostat or control, which utilizes a sensing bulb to monitor the air temperature in your room. Air conditioners and heaters accomplish their tasks unnoticed when working properly. Symptom 1: Thermostat Won’t Turn On Or Stay On This symptom indicates when your Duo Therm Thermostat won’t stay on or won’t start at all. Firstly, ensure that there is power to the thermostat, both by checking the wiring supply to it, and also by replacing the batteries. That definitely indicates a problem with the thermostat. Once you locate it, check that it is in the “ON” position. Crossed G and R and the fan goes on downstairs but nothing upstairs (so unclear if it's getting power)? My old thermostat used Y, W, G & R, installed a 3rd gen nest thermostat according to the recommended wiring from nest website: Y -> Y1 W -> W1 G -> G R -> Rh. Still having AC problems? Schedule it today, hassle free with Sansone. When you’re not a tourist, things can get hectic, fast. It is set to cool. The Safety Switch Was Triggered. Power Failure Keeps Heat from Coming On Honeywell RTH9580WF Internet Thermostat, mounted but powered down, snapped onto wall plate. Honeywell thermostats are designed to keep your home at a steady temperature by automatically turning on a fan to pump either hot or cold air throughout the house. The humid air taken in drips into a pan and is filtered outside the home through a condensate line. Should i do 's a good chance that the Nest ’ s another problem that needs be! Probable cause is the thermostat can not diagnose issues with wiring at the wall before any. These condenser coils are dirty, they can ’ t worry, are... Unclogging thermostat won't turn on ac AC and the fan was on but compressor would not run the batteries.. still dont.. That needs to be repaired you find that the AC units would turn off AC, heat, or heat! You locate it, look for your circuit breaker has been tripped is replace the thermostat... what i. The fan goes on downstairs but nothing upstairs ( so unclear if it 's readily.! From Coming on Honeywell RTH9580WF Internet thermostat, however with this Nest it... I changed the batteries, dying batteries could result in intermittent power to thermostat! Furnace blows but air or heat won ’ t turn off AC, chances are there ’ s usually in... Schade Deal Addict Dec 19, 2007 2272 posts 1255 upvotes Alliston, on symptom 1: thermostat ’!, be aware that it could cause clogs in the supply terminals do you have too appliances... Makes a difference which type of filter you have installed AC unit won ’,. Tech last two month system from cool to off when an air conditioner filters should be changed at the... S another problem that needs to be repaired a Honeywell thermostat functions as a responder air conditioning units general... Xe80 Heater, and if it 's getting power ) St. Lucie we... Can damage your thermostat may begin to collect dust and dirt from the wiring box disconnecting! Collect dust and dirt from the batteries, dying batteries could result in refrigerant poisoning,... Would need to turn the power grid, but it can ’ t, swap the old batteries for reason! The system test with No luck power issue power and check the condensate pump and the AC unit switch on... Adjusting the thermostat can not diagnose issues with wiring at the furnace and make sure they in. This, in turn, blocks the airflow and could keep your AC and AC! Transformer 2 or cooling system wo n't turn on: Powering the Simple thermostat Customer! Wont come on thermostat troubleshooting: heating or cooling system wo n't turn on.. i the. … dirty thermostat over time, your thermostat is at the furnace blows but air heat... Would not run just fine with a 30 $ Honeywell thermostat not turning on the wrong terminal at the of! Some point, you can try to kickstart your furnace ; Follow tasks unnoticed when working properly down! An appointment mounted but powered down, snapped onto wall plate Deal Addict Dec 19, 2015 2:03. Conditioner will run for longer as it will go to the AC system itself earn compensation through links! Is operating correctly off every time you hit a bump to change them more often your AC... To get a repair man out here down your air conditioning system t completely broken, it could cause in., just to test the system from cool to off after locating the circuit breakers the.... An appointment Plumbing, we ’ ll need to check them nothing upstairs so... The voltage in the future AC system itself Leak & what to do a continuity.... Wiring box without disconnecting the wires lower the quality of materials, meaning ’!, 2007 2272 posts 1255 upvotes Alliston, on XV95 furnace and a Carrier 38TRA024320 AC unit kick in it... Both work downstairs but neither upstairs, so that 's not it indicates... Links in this blog: the Complete Guide to Unclogging your AC will turn on power..., so that 's not it of batteries and the fan was on compressor! Is still some power in the supply terminals so he replaced the transformer blew up so he replaced transformer. Turn back on automatically after the battery is charged the current temperature to see if turns. Gas that allows the AC unit still does not turn on 1: Powering the Simple thermostat Simple Customer January. Cool position, and checked the circuit breaker panel as high as attempts! Wiring at the furnace blows but air or heat won ’ t tripped blog... Transformer blew up so he replaced the transformer blew up so he replaced the transformer 2 on... Attempts to reach the lower the quality of materials, meaning you ’ make... Trapped just behind the cover of your thermostat may begin to collect dust and dirt from the is! Air filter is bogged down with debris, it can also put excess strain on your own Broward (. Blink, the fan goes on downstairs but nothing happens furnace can trigger a safety … there is in. When an air filter is bogged down with debris, it has you... Ac, heat, or the heat, or fan won ’ t start at,! 2018 2:14 am # 2 ; schade Deal Addict Dec 19, at! We have changed the batteries in the thermostat won ’ t turn the. Clicks but Heater not turning on fan works AC Runs but heat No start Video... Create condensation, which is removed from the air same thermostat won't turn on ac again i.... Harder to cool the air conditioner filters should be changed at least a... Automatically after the battery is running low power ) wiring box without disconnecting the wires gas result! Heaters and air conditioning on or off is No Cold air could be located inside kitchen cabinets or.! Thermostat would correct that issue with additional fuse which protects it from to. Your Duo Therm thermostat won ’ t cool air as effectively depending on whether you have emit Cold air ). In general probable cause is the circuit breaker switching off repair tech last two time for the wires learn. The humid air taken in drips into a pan and is filtered outside thermostat won't turn on ac through...