If your Honeywell thermostat display not working, then there are quite a few possibilities that you’ll need to tackle.
By the end of this guide, you will know everything there is to know about the issue as well as proven solutions to work with!
Your thermostat display could refuse to work if you don’t close the control door completely. If it’s not the access door, you’ll need to inspect the position of the breaker switch, inspect the thermostat configuration and check for sensor issues.
Let’s now jump in straight to the solutions and find out what exactly happened to the display.
How To Fix Honeywell Thermostat Digital Display Not Working?
The fix sequence includes several solutions that we highly recommend being applied in the order that they are listed.
This way you’ll cover everything that could be responsible for the non-working display and hopefully solve the issue right away!
Solution #1 Identify A Non-Working Unit
The very first thing to do is identify whether your Honeywell thermostat is entirely broken or simply the display is not showing anything.
We assume that you’ve connected your thermostat to your smartphone application via WiFi and if it is still connected while the display is not working, it means that you have full control over it.
Note: If you cannot control your thermostat with the app, it does not mean that it is broken right away. In such a case, jump to solution #2.
To identify if all else is working well, but the display, follow the steps below:
- Open the Honeywell app on your smartphone.
- Turn ON the heat and increase the temperature to MAX.
- Stop the heat, and turn ON the cooling.
- Check if FAN is working.
In case you’ve identified anything else that’s not functioning properly, there is a high chance of a power problem.
To resolve possible power issues, re-connect ALL cables, change the wall outlet and remove any power dividers and change the AA batteries with new ones!
Solution #2 Internal Maintenance
Regardless of if it’s only the display or the entire thermostat is not working, here are a few steps to apply that will definitely resolve any problems related to
To proceed, follow the steps below:
- Turn OFF the thermostat.
- Remove the top cover by unscrewing the 4 screws at each end of the thermostat.
- Get a slightly wet napkin and remove all dust from the internal part of the thermostat.
- Close all access doors completely!
- Close the compartment and screw it tightly.
When ready, make sure that the internal hardware that you’ve cleaned is DRY before you turn on the thermostat. Lastly, test and check if the display will turn on.
Solution #3 Flip The Breaker
Often, the breaker in the HVAC can get tripped and you will have to switch it back on.
This usually happens in order to protect your system and should NOT be removed under any circumstances.
Simply press the breaker’ switch to the ON position in your HVAC panel, to enable the system and fix the display of your thermostat.
Note: If the circuit breaker switch is ON, we recommend turning it OFF and after a few moments reverting it back to ON position.
Then test the thermostat display again.
Solution #4 Factory Reset The Thermostat
If your Honeywell thermostat display not working you can perform a factory reset which will address any possible software problems.
If you own the digital version, you will have to perform a battery flip-flop in order to reset the thermostat.
Note: All other models have a dedicated reset button that you can use to perform the reset.
Here is how to factory reset a digital Honeywell thermostat:
- Open the panel in front of the battery compartment on the thermostat.
- Eject the batteries and insert them the other way around.
- Wait for 5 seconds and take them out one by one.
- Insert the batteries in the correct position and put together your thermostat.
Once you turn on the thermostat the display should light up and provide you with visuals of the initial setup configuration. If not, continue with the next step.
Solution #5 Check For Sensor Issue
It is possible that the mercury switch is not reading the temperature you applied correctly. This can cause your system to power off and on over and over again.
In most cases, these symptoms are related to the temperature sensor fault, which will definitely prevent the display controls or disable the visual entirely.
If that’s the problem your thermostat might not be cooling properly or the device would not be able to reach the temperature you applied.
In that regard, we’ll focus on detecting sensor issues.
Here is how to check if the temperature sensor is accurate:
- Make sure that your thermostat heat is all the way up!
- Graba thermometer and measure the actual temperature near your thermostat.
- Check if the set temperature and the actual temperature align.
If both values do not align perfectly (there should be 1-2 degrees alloweness) then you’ve got a sensor issue, which is not that expensive to be replaced.
This way you’ll avoid replacing the entire thermostat.
Next, we’ll review cases in which people report that they cannot adjust the brightness of their display which if lowered to the minimum can make the impression of a non-working display.
How to Fix Honeywell Display Light Not Working?
If you take a quick look at the back of your thermostat, you’ll notice that there’s a light that is called a backlight.
Sometimes the light turns on and others don’t. That happens because the thermostat fails to turn your AC on.
The simplest solution to this issue is to just reset the thermostat and here is how:
1. Replace Batteries
If you already have replaced the batteries as it says above this, then you don’t need to do it again.
You shall do it only if the batteries that are currently in the thermostat are dead.
2. Reset the Circuit Breaker
Turn OFF your thermostat, then locate the circuit breaker responsible for the HVAC system and turn it OFF as well. Wait for about 1 minute and put it back ON.
3. Reconnect with WiFi
Make sure that the Honeywell thermostat is connected to the WiFi and the connection is reliable and secure.
4. Increase the Brightness
If your thermostat’s display light is too lowered, it is possible that the light is working but you’ll need to increase the brightness.
Once you’re done with these steps, restart your thermostat and check if the display will work. If it doesn’t, well, your display might just be broken, and you’ll need a replacement.
To fix a non-working display on the Honeywell thermostat, first, try to increase the brightness. Then change the batteries to perform a reset and make sure that the circuit breaker switch is flipped ON.
Lastly, you can carry out an overall inspection plus cleaning of the internal hardware and if nothing works, bring the thermostat for repair.
Read Next: Why Is My Honeywell Thermostat Heat Not Working On Auto?
After learning all about why the Honeywell display not working, we hope that we’ve helped you fix your problem.
If however, the problem is still there and you don’t think that you’ll need repair service, you can contact Honeywell customer service for another round of troubleshooting.
Kevin has over five years of experience working in various Tech startups and providing Technical solutions. He has contributed to many Tech publications and websites.