honeywell home pro series won't turn on

Wondering why the Honeywell Home Pro Series won’t turn on? We got you covered! 

Users experience the worst situation when Honeywell thermostats do not turn on, no matter how reliable and user-friendly they are.

Therefore, if you’re having the same problem with your Honeywell Home Pro series, keep reading the guide to know everything you need.

Different factors may prevent Honeywell Home Pro series thermostats from turning on, including weak batteries, a defective power supply, loose wiring, or dirty air filters.

The solution doesn’t require any technical steps but a proper inspection is required! Now let’s find out more detail about not turning on the Honeywell thermostat:

Why Is the Honeywell Pro Series Thermostat Not Turning On?

why is it not turning on

If your Honeywell thermostat is not turning on, then it could happen because of different aspects, but the most common one is the unavailability of a power supply.

This often happens when the HVAC circuit breaker trips automatically and the device can’t turn on!

However, besides problems with the power supply, there are a lot of other things that will eventually cause power issues so let’s unwrap everything:

  • Loose Honeywell Thermostat Wiring
  • Faulty C wire of Thermostat
  • Clogged Filter of Air Conditioning System
  • Thermostat System Bug
  • Dead or Low Thermostat Batteries
  • The indoor unit opened Doors, especially Furnace
  • No power to Furnace or Air Conditioning Unit

Now that we have discussed the causes, we can troubleshoot the thermostat effectively!

Honeywell Home Pro Series Won’t Turn On – Fixed!

why is it not turning on

We are going to discuss the troubleshooting methods that are very easy to implement and don’t require any technical knowledge to fix the issue.

It’s only important to completely follow the guide without skipping any of the solutions.

Let’s jump right in!

Solution #1 Check The Circuit Breaker

circuit breaker

The very first thing you have to do is to check the Honeywell thermostat Power Supply

Maybe the power is not coming in the thermostat and that’s why it is not powered on.

Usually, a tripped circuit breaker, an overloaded circuit, or a loose power wire causes this complication!

Solution: You first need to restore the thermostat power!

This is the way to restore the Honeywell thermostat power:

  1. Turn OFF the Circuit Breaker power.
  2. Stay aside and wait for 5 minutes.
  3. Check the wiring from the circuit and thermostat.
  4. Make sure no wire is defective, especially their ends.
  5. Then, turn the circuit breaker on.
  6. Next, turn on the thermostat and check if it turns on.
calling a technician

If your thermostat won’t turn on, your home’s circuit breaker may be overloaded.

To verify that, go and see whether the breaker is tripped; if it is, that will be the reason why your device isn’t turning on. Simply call a technician to fix this issue!

Note: If the breaker is not tripped, then try the next solutions in the guide!

Solution #2 Clean The Air Filters

clean air filters

Cleaning the Air Filters is very important to prevent yourself from experiencing different issues with your Honeywell thermostat.

Over time the conditioning air filters will get clogged easily and if they are not cleaned or replaced, the air will not circulate from the vents. 

As a result, when the air can’t easily circulate, the thermostat will not get an appropriate reading of room temperature and doesn’t perform well.

Sometimes I might not even turn it on! Simply clean the air filters of your AC unit to fix the issue!

That’s how to clean the air filters AC:

  1. Unplug the AC from the Power Source!
  2. Then, carefully remove the Air Filters from your unit.
  3. Wash the filters under water and soak them in a mix of lukewarm water.
  4. Leave them in the washing liquid for half an hour.
  5. Then, wash the filters under to clear the dirt and let the filters dry completely.
  6. Once the filter dries, connect them back to AC and turn it on.
turn off then on thermostat

After cleaning the air filters, power cycle your thermostat and check if it turns on.

If not, then move on to the next solution!

Note: Replace your AC air filters at least every year or wash them monthly!

Solution #3 Inspect the Furnace Doors

closed furnace doors

Most of the time, the thermostat stops working, or its screen goes blank whenever the furnace door is opened.

The thermostat is indirectly connected to it and when the furnace door is left open or it is turned off, the thermostat will begin to malfunction. 

There is a chance that your thermostat isn’t turning on because of the furnace!

All you have to do is to check your Furnace Door and make sure it is closed as well as the Furnace Breaker is turned on and working properly.

When you’re ready with the inspection check whether the Honeywell thermostat is now going to turn on!

Tip: Perform maintenance of the furnace once every year to maintain its performance!

Solution #4 Replace The Thermostat Batteries

changing thermostat batteries

Perhaps the battery set in your device is dead and that’s why the Honeywell Home Pro series thermostat won’t turn on.

For the pro series, the batteries only serve as a backup since the device is connected to the AC line, but when they are defective we can expect the worst.

It’s simple to replace the batteries in the thermostat device:

  1. Turn off the Honeywell thermostat Power Breaker
  2. Hold the thermostat and disconnect it from the base. 
  3. Locate the battery compartment in your thermostat. 
  4. Take out the old batteries and insert 3 x AA alkaline batteries
  5. Connect the thermostat back to the base and turn it on. 
duracell power boost

You should always prefer reliable brand batteries when replacing thermostat batteries, so we recommend getting DURACELL Batteries!

With these bad boys, you won’t be wondering whether the batteries are dead for quite a long time so you’re missing out!

After replacing the batteries in your thermostat, make sure to check if it turns on. In case not, then try other solutions from our guide! 

Solution #5 Check For Loose Connections!

check the loose connections

If your Honeywell thermostat is still not turning on, then now you have to carefully look at the thermostat wires.

There is a possibility that any of the thermostat wires got faulty or loosely connected.

In addition, the device’s power C cable could not be attached properly or is defective and that’s why the Honeywell thermostat is not turning on.

An inspection is necessary!

This is the way to check the Honeywell thermostat wires connection:

  1. Switch off the power from the Circuit Breaker!
  2. Hold the thermostat screen and disconnect it from the base.
  3. Remove the thermostat C (white) wire from the base.
  4. Next, remove the Rh or Rc (red) wires from the base. 
  5. Then carefully check each wire and ensure that the wires’ ends are straightened.
  6. Connect all the wires tightly back to their correct connector on the base. 
  7. Fix the thermostat screen properly with its base.

After checking the wires, turn on the thermostat and check if it turns on. If not, then the wires are faulty and to fix them you’ll need to call a professional.

Solution #6 Factory Reset Honeywell Thermostat 

factory reset thermostat

When there is no workable solution for the issue, a simple Factory Reset on the Honeywell thermostat should be able to restore the functionality.

Your device may have a system bug, which is why it is malfunctioning and not turning on so let’s learn more!

Keep in mind that the reset will delete all of the thermostat’s pairing and settings, so you’ll need to configure them again.

Don’t worry, though; configuration only takes a few minutes! 

It’s very simple to factory reset the Honeywell thermostat, so follow the steps:

  1. Turn off the thermostat Power Supply
  2. Remove the thermostat batteries
  3. Now put the positive battery on the negative side!
  4. And the negative battery on the positive side to reset the device. 
  5. Wait for 20 seconds
  6. Then take out the batteries and properly insert them!
  7. Turn ON the Honeywell thermostat.
read device manual

After the reset, turn on your device and set up all the settings.

In case your thermostat doesn’t have batteries and is set up via hardwire then consult your device manual to know the correct way to reset your device.

Good luck!

Quick Recap:

Whenever your Honeywell home pro series won’t turn on, turn on the circuit breaker, replace the thermostat batteries and check the thermostat wires!

The next step is to clean the AC Air Filters and close the furnace doors before performing a Full Reset.

Make sure to follow us for more guides on thermostats!

Nicole B