[11 Ways] – How to Fix Nest Thermostat Not Turning On AC

Did your Nest thermostat AC just stop working all of a sudden and is not turning on now? This hurdle may frequently occur without any obvious reason. However, fixing this is pretty easy and won’t require much of your time.

But, why nest thermostat not turning on ac compressor?

Certain problems concerning your Nest thermostat may not turn on your AC compressor. The most common of which include low battery and poor power supply. Moreover, other causes include inappropriate wire connection, and problematic Wi-Fi connection. However, sometimes your Nest thermostat and AC compressor may not be compatible enough to work together.

So, keep reading to dive into some of the most straightforward and useful fixes for Nest not turning on AC. We shall talk about the details of some of the most likely causes for it too.

how to fix nest thermostat not turning on ac

Why is my nest thermostat not turning on ac?

Before heading to the fixes, it’s essential first to recognize the main issue behind your thermostat is not turning on the AC.

Here are the causes why your Nest not turning on AC:

  • Low-powered thermostat battery
  • Dust within your thermostat
  • Inappropriate location for your Wi-Fi device
  • Low power supply
  • Loose wiring
  • Running out of the Heating, Ventilation, and Air
  • Conditioning System (HVAC system)

How to fix the Nest thermostat not turning on AC?

Fixing your Nest thermostat and not turning on AC may be hectic at times when you don’t know what the actual cause for it is. In such a situation, you may simply follow the guide below step-by-step you get rid of the problem.

Here are the methods to fix the Nest thermostat not turning on AC:

1. Check the battery of your Nest thermostat

The first and most important step in fixing your thermostat is to check its battery. Sometimes, your thermostat may not turn on its AC due to low powered battery. This primarily happens when they have less than 3.6 volts to function.

The thermostat’s battery usually gives up when the voltages required reduces. The only solution here is to either charge them up and if not possible then replace them with new ones.

Also read: Nest Protect Battery vs. Wired

2. Check the wires of your Nest thermostat

The next hack is to check the wires of your Nest thermostat. As you know, many wires within your Nest’s system can loosen or be torn off due to overuse. Moreover, they need to be attached to the right terminal.

When you have a new Nest thermostat, and its AC is not turning on, then the chances are that you may not connect its wire to the right terminal. The most important wire in such a situation is the RC one, the Red Cooling wire.

Therefore, remove the Nest thermostat from the wall and inspect it carefully, especially the red Cooling wire. Ensure that you have inserted the wire at the right terminal and it’s not torn, loosened, or burnt.

Sometimes, you may not have an RC wire, then look for the RH or R wire.

In addition, do check the G, Y, and the C terminal.

3. Check the location of your Wi-Fi router

If the battery and wires of the Nest are fine, then poor internet may cause it not to function well. So, now check the location of your Wi-Fi router.

If your Nest thermostat and Wi-Fi router are far from each other then chances are that your thermostat may not receive enough signals to work well, and thus it may not turn the AC on. To resolve this problem, place your router close to the Wi-Fi router for efficient results.

Also Read: How to connect nest thermostat to wifi

4. Clean the dust from your Nest thermostat

If placing your Wi-Fi router close to the Nest thermostat didn’t help you in any way, then chances are you may accumulate dust within your Nest thermostat.

This may indirectly interfere with the functioning of your thermostat. Moreover, the dust may demand more power for your thermostat, thus reducing its efficiency.

Therefore, it’s necessary to clean it regularly. To do so, simply remove the thermostat’s faceplate and then clean the thermostat gently using a microfiber cloth, canned air, or soft brush.

5. Check the quantity of the voltage

Next, the hack is to ensure you receive enough power supply for your thermostat to function efficiently. To do so, you may simply find out the voltage it’s receiving. If it’s 3.6 or more, then it’s perfectly fine.

However, if it is below 3.6, then here’s the main problem. This may even occur due to poor battery or wiring too. The power surge is the main cause, though. So, in such a case, you must wait until the problem is resolved.

Also, double-check the voltage once you get back the power.

6. Check your Nest thermostat’s circuit breaker

If all the above hacks didn’t work for you, then the next step is to check your Nest thermostat’s circuit breaker. Sometimes, it may trip suddenly without you even knowing it; therefore, you would think your thermostat is on.

So, whenever you see your thermostat not turning on AC, check if your thermostat is on or off. If it is off, head to the electric panel and turn on the Nest thermostat’s circuit breaker.

7. Change the Settings on the HVAC system

Sometimes there may be an error on your HVAC system due to overworking. In such a situation, HVAC runs continuously and causes your thermostat to read the room temperature inaccurately.

So, the solution for such a hurdle is to set your HVAC to auto. This will not keep your HVAC on throughout the day. Also, this should include your boiler, heater, fan, and AC. By doing so, your HVAC will only activate when the room temperature goes above or below the required temperature.

Also Read: What causes Nest thermostat not turning on heat

8. Check the compatibility of the Nest thermostat and the AC

In some rare cases, there’s a possibility that your AC is not compatible with the Nest thermostat. For example, the Nest thermostat may not function well with high voltage systems.

So, in changing the HVAC settings that didn’t work out for you, straightforwardly contact the Nest manufacturer and distributor to check if you have any compatibility issues. If you have such an issue, you may need to replace the AC or the thermostat.

9. Restart your Nest thermostat

Restarting your system is the easiest troubleshooting step that refreshes your system in no time.

Therefore, you may simply continue your Nest thermostat, which will temporarily remove all the errors from the system.

So, try this hack before heading to the next one.

Learn more about How to reset Nest thermostat without password

10. Try activating the Cooling mode from the Nest app

Activating the Cooling mode from the Nest app will help you turn on your AC from your Nest thermostat.

Here are the steps to activate the Cooling mode from the Nest App:

  1. Firstly, head to the Nest app and tap on the Nest thermostat button is present on your Home screen. Note this button shows your thermostat’s current temperature.
  2. Next, tap on the option Heat present at the bottom left of your screen.
  3. As you do so, you’ll see a few options like Heat, Heat-Cool & Cool. Tap on Cool to set your Nest thermostat to cooling mode. This may increase your thermostat’s current temperature/
  4. Now, move the cursor on the temperature to lower the temperature according to your need.
  5. Lastly, exit the Nest app.

Also Read:

11. Try activating AC from the Nest Thermostat

After activating the Cooling mode, you may now start your AC from the Nest app.

Below are the steps to activate AC from the Nest app:

  1. Firstly, head to the Main menu by pressing your thermostat’s ring.
  2. Next, turn the wheel on the ring to the thermostat icon.
  3. Now push the icon to select it.
  4. As you do so, you’ll see a few options like Heat, Heat-Cool & Cool. Tap on Cool to set your Nest thermostat to cooling mode.
  5. Your AC will now start working.

Also Read: Why is my nest thermostat not cooling to set temperature

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Your Nest thermostat may not turn on due to poor power supply, low battery, loose wires, improper Wi-Fi connection, and incompatibility between the Nest thermostat and the AC.

Luckily, you may fix all these problems. Therefore, in this in this article, we have discussed the most straightforward hacks for you to get rid of all these hurdles in no time.

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