Why Is My Nest Thermostat Not Turning on the A/C?

Nest thermostat with equipment detection screenNest thermostat with equipment detection screen

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A Nest thermostat is a must for any Smart Home, but what happens when your Nest won’t turn on the A/C? There are several reasons as to why your Nest isn’t working properly and not turning on the A/C.

The most likely reason for your Nest thermostat not turning on the A/C is that it doesn’t get enough power or has a low battery. There could also be issues with your Wi-Fi, leading to your Nest not turning on the A/C. However, these are just two of the most common issues.

It’s time to put an end to being hot and bothered and find a solution to your Nest Thermostat and A/C issue. Keep reading for what you need to know on why your Nest Thermostat isn’t turning on the A/C.

Why Your Nest Thermostat Isn’t Turning on the A/C

There are multiple reasons as to why your Nest Thermostat isn’t turning on the A/C. Luckily, most of them are easy fixes and don’t require a ton of work.

Here are six reasons why your Nest thermostat isn’t turning on the A/C:

  • Incorrect thermostat wiring
  • Not getting enough power supply
  • Wi-Fi location issues
  • Dust in your thermostat
  • Continuous running of the HVAC system
  • Thermostat battery at the end of its lifespan

What To Do When Your Nest Thermostat Won’t Turn on The A/C

You’re not alone in your frustration. Many Smart devices have similar issues. This issue is just particularly awful because it’s literally making you sweat.

Next up, we’ll discuss how to fix these problems:

  • Low battery
  • Incorrect wiring
  • Not enough power
  • Wi-Fi Router Issues
  • Nest is dusty
  • Continuous running of HVAC

Low Battery

It’s possible that your Nest thermostat just has a low battery. This is a good place to start. Although most Nest batteries last quite some time, it’s possible that your battery gave out early.

Incorrect Thermostat Wiring

If it doesn’t follow the command to turn on or off, please check the charging by blinking the light. If it turns red, you can charge it. It’s the common reason that makes the thermostat unresponsive. It is also possible there is something wrong with the wiring. Once you wired correctly, it is going to work as normal.

Not Enough Power Supply

The easiest way to know if your thermostat is getting enough power supply is to go to the settings and find out the number of the voltage. It should be 3.6 or above. If it is low, you should examine the wiring or battery level.

In the event of a power outage, your Nest battery will keep it functioning for a little while. But it’s important to double-check the power supply after an outage to make sure it’s getting enough juice.

Wi-Fi Router Issues

One of the most common mistakes people can make is relative to Wi-Fi. Your Nest thermostat is unable to connect to the Wi-Fi because of an incompatible router. The location of your router and Nest might also be to blame. To ensure this isn’t the issue, the router should be no more than a room away.

Dusty Nest

Dust is one of those things that’s just always lurking around in our homes, waiting to cause problems. And it can with your Nest. Dust gets inside the thermostat that can decrease the efficiency. It also takes more energy while running your A/C. As a result, it decreases the battery lifespan and a sudden failure of the Nest thermostat to connect with the A/C.

Continuous Running of The HVAC System

If your HVAC system is set to run continuously, it could cause faulty temperature readings with the Nest sensor. Set your HVAC to auto to give the Nest a chance to read the room. 

Tripped Circuit

If your Nest is completely off and not responding to turn on the A/C, it might be. Double-check the rest of your appliances to see if they’re working. And if not, a trip to the circuit box is all you need to make sure your Nest is back up and running.

Final Thoughts

There are a lot of reasons why the Nest thermostat won’t turn on the AC. It could be because of poor power supply, dirt in the thermostat, router placement, and many other reasons, all of which we’ve listed above.

While it’s easy to panic when the A/C isn’t turning on- who wouldn’t- more than likely, one of the issues discussed above is the reason behind the issue. And, they’re all fairly simple fixes. Start with the low battery and work your way through our list. Hopefully, you’ll be cooled down in no time.

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