If your Nest thermostat screen has suddenly gone blank/black and you’re not sure what to do, keep reading.
In this post, we explain the reasons behind this issue. We’ll also walk you through some steps to get your Nest thermostat back on. Let’s get right into it.
Here are common reasons your Nest thermostat may display a black/blank screen:
- The screen isn’t properly connected to the base of the device.
- Low battery power.
- Your circuit breaker isn’t sending power to the thermostat.
- Your Nest thermostat is incompatible with your heating system
- You didn’t put your Nest thermostat wires in the appropriate connectors.
- There is a blown fuse in your electrical panel.
- Your Nest thermostat is faulty.
Now, let’s look at what you can do to fix this problem.
Nest Thermostat Black/Blank Screen: How to Troubleshoot
1. Charge Your Nest Thermostat with a USB Cable
Your Nest thermostat display will go blank if the batteries are low/completely drained. So, if your Nest thermostat screen is black/blank, chances are the batteries are low, and you’ll need to replace or charge the batteries to fix the problem.
If you have a Nest thermostat model that uses AAA alkaline batteries, replace them with a fresh set of the same batteries.
But for Nest Thermostat E and Nest Learning Thermostat, the batteries are built-in, and they charge automatically via your HVAC system. But for some reason, your Nest thermostat might fail to charge automatically, and this may keep the thermostat screen blank. So, you’ll have to charge the thermostat with a USB cable.
Follow the steps below to charge your Nest thermostat with a USB cable:
- Remove the Nest thermostat’s display from the base.
- Then insert a USB cable into the USB port and the back of the thermostat’s display.
- Put the other end of the USB cable in a charger and plug it into a power outlet. Avoid using a computer to charge your Nest thermostat.
- The Nest thermostat screen should now turn on. When the screen lights up, you will see a message instructing you to connect the display to the base. Push down the display onto the base until you hear a click.
Note that your Nest thermostat may charge for about an hour, especially if the battery is very low.
After charging your Nest thermostat with a USB cable, you can start using it. However, you may need to call a technician to fix the charging problem in your thermostat. Read more about Nest thermostat charging issues.
If this fix doesn’t help with the blank screen problem, continue to the next step.
2. Fix Your Nest Thermostat Display onto the Base Properly
Your Nest thermostat screen will stay blank if the device’s display isn’t attached correctly to the base. Check the screen and ensure it is properly seated on the base.
Here’s how to do this:
- Remove the Nest thermostat’s display from the base by pulling it out.
- Then check whether any cables are sticking out of the wall. If you find any wires protruding out of the wall, tuck them back into the wall.
- Next, arrange the base connectors and the Nest thermostat display over the base.
- Now, push down the display on the base until you hear the display produce a clicking sound.
3. Ensure Your Nest Thermostat is Receiving Power from the Circuit Breaker
If your Nest thermostat screen is still blank/black, chances are it’s not receiving power from the circuit breaker. This may occur when the circuit breaker isn’t properly turned on.
Take the following steps to fix this issue:
Turn off your Nest thermostat’s circuit breaker by moving the switch to the OFF position.
Now, move the switch back to the ON position to switch the breaker on. While turning on the circuit breaker, ensure you pull the switch to the end of the ON position—to ensure it is properly switched on.
Now return to your thermostat to see if the problem is resolved. If not, keep reading.
4. Confirm that Your Nest Thermostat is Compatible with Your Heating System
The Nest thermostat is incompatible with high voltage, millivolt, and proprietary heating systems. If you use the Nest thermostat with any of these heating systems, it may not get sufficient power to charge its battery.
Other heating systems, apart from millivolt, proprietary, and high voltage systems, work properly with Nest thermostats.
To help you identify whether your heating system is a high voltage, millivolt, or proprietary, we’ll try to describe them:
High voltage Heating System: Most high voltage heating systems are radiant systems like electric baseboards. They often have 110,115, 120, or 240VAC labeled on them. These heating systems are usually built on the wall and may have about 2-4 thick wires sticking out of the thermostat when you install it. To connect a thermostat to a high voltage system, you’ll first need to attach wire nuts to the heating system wires.
Millivolt Heating Systems: A millivolt heating system can be a wall-mounted or floor-mounted heater that is powered by natural gas or electricity. Even when a millivolt system uses electricity, it still provides less power than the required amount for the Nest thermostat.
Proprietary Heating System: If your HVAC system only has 2 wires when you have both heating and cooling systems, your heating system is most likely proprietary.
If you discover that your heating system is millivolt, proprietary, or high voltage, you might need to replace your Nest thermostat with a compatible alternative. That said, an installation expert can help you rewire your proprietary heating system to make it compatible with the Nest thermostat.
5. Re-insert Your Nest Thermostat’s Wires Appropriately
If your Nest thermostat screen fails to turn on when you just finished setting it up, you may not have connected your thermostat wires correctly. Your Nest thermostat wires need to be properly inserted into the base connectors for the device to function effectively.
If your thermostat stays blank after you’ve just set it up, you might need to re-insert the wires into the connectors.
The following guide will help you do this:
- Switch off your HVAC system at the fuse box. If the HVAC system uses a switch, you should also turn that off. This will prevent your thermostat and HVAC system from getting damaged as you re-insert the thermostat wires.
- Next, remove your Nest thermostat display from the base.
- Pull one wire out of the base connectors and inspect it for any crookedness or corrosion. The wire should be clean and straight. In addition, the wire must be 1cm long. If your thermostat wires are crooked or rusty, cut and re-strip them.
- Now, insert the wires back into the base connectors. Ensure that all the connectors stay down before you fix the display back onto the base. If a connector isn’t completely down, you may not have inserted the wire into the connector appropriately.
- Once all your thermostat wires are fully inserted, push down your thermostat’s display over the base until it produces a click.
- Now, switch your HVAC system and thermostat back on. If a red light blinks from your thermostat after you fix its display onto the base, the battery is currently charging. However, if you can’t see any red light flashing from the thermostat, you may have inserted the wires into the wrong connectors. Consult your wiring diagram and ensure that you follow the diagram strictly.
6. Inspect your HVAC System and Thermostat’s Wiring
If your Nest thermostat screen remains blank after trying other fixes above, there might be a blown fuse in your HVAC system. You can ask a professional installer to fix this issue for you. The installation expert will inspect your thermostat’s wiring and HVAC system and repair any faults.
7. Try Using Your Old Thermostat
If none of the solutions above fixes your Nest thermostat, the device may be damaged. To confirm this, install your old thermostat again to see if it works.
If your old thermostat isn’t working either, there might be a blown fuse in your HVAC system. Ask your HVAC technician to repair your HVAC system.
However, if the old thermostat works perfectly with your system, your Nest thermostat might be seriously damaged.
If you suspect that the Nest thermostat isn’t working because you aren’t installing it correctly, consult an installation expert.
You can hire a professional installer and ask them to set up your Nest thermostat for you. The professional installer will tell you if the thermostat is faulty or needs servicing.
8. Reach out to the Google Nest Support Team
If you don’t want to hire an installation expert to set up your Nest thermostat for you, you can call the Google Nest support team. They’ll walk you through the installation process and ensure that you set up the thermostat properly.
The troubleshooting tips in this post should help you fix your Nest thermostat screen problem. But if the problem persists after applying all the fixes, try contacting Google Nest Support for help.