Honeywell Thermostat Not Turning On After Battery Change? Do This

Honeywell Thermostat Not Turning On After Battery Change

Unfortunately you may have noticed that your Honeywell thermostat is not turning on after you changed the batteries. You are not alone, many Honeywell thermostat users often experience this problem.

Your Honeywell thermostat plays a crucial role in controlling your home’s HVAC system seamlessly. This explains why it can be annoying when your thermostat stops functioning when you change the batteries. This article discusses common reasons for your Honeywell thermostat not turning on after replacing batteries and how you can fix the problem.

Why Honeywell Thermostat Not Turning On After Battery Change?

Reason 1: Incorrect battery type

Putting in incorrect batteries is a common cause for Honeywell thermostat not turning on after a battery change. You might be using the wrong batteries and that’s why your Honeywell thermostat is not working after a battery replacement.

The new batteries you bought might not be sufficient to power your thermostat. Check to see if you have the correct type of batteries. Ensure that they’re the recommended batteries.

Honeywell thermostats only use normal AA/AAA alkaline batteries. If you insert any other type of battery such as lithium or rechargeable batteries into the thermostat, the device won’t function.

However, not all AA/AAA alkaline batteries in the market have same quality. Even if you can buy the expected batteries, make sure they are of good quality.

Inactive or substandard batteries may cause non-functionality problems. So ensure that the batteries are active and are of high quality batteries such as Energizer, Duracell, and the like.

How to fix: choose the right battery type

Check and ensure that the new batteries are AA alkaline batteries.

  1. To do so, find the battery pack for your new batteries. AA alkaline batteries have a logo ‘AA alkaline’ on the battery pack.
  2. If you don’t see the AA alkaline logo, you might have inserted the wrong type of batteries into your thermostat. It’s, therefore, advisable to remove the batteries and get new AA batteries.
  3. Check inside of the battery compartment to know what voltage your batteries should be. Normal voltage of AA alkaline batteries is 1.5V.
  4. Ensure that you’re using the recommended AA alkaline batteries. If your Honeywell thermostat is still not turning on, move to the next step.

Reason 2: Mixing old batteries with new ones

It’s likely that you mistakenly mix old batteries with new ones, causing your Honeywell thermostat not to turn on or stop functioning.

The differences in charge levels between the new batteries and the old ones often cause issues with your thermostat.

The differences in charge levels can cause battery leakage, decrease overall performance, and make your thermostat fail to function or show incorrect temperatures.

How to fix: replace all batteries

  • If your thermostat batteries are low, make sure to change all of them for the best performance.
  • Always avoid mixing up old and new batteries. Always bring all new batteries when doing a battery replacement on your Honeywell thermostat.
  • Ensure to replace all batteries in your Honeywell thermostat at the same time. You can’t replace one and leave the other.
  • If you change one battery and leave another one, your thermostat won’t work.
  • You should insert a new pair of batteries at the same time and assess if your thermostat functions well again.

Reason 3: Batteries installed incorrectly

At times, your thermostat won’t function because you might have installed the batteries incorrectly.

Despite being a long-term Honeywell thermostat user, it’s possible that you did not place the new batteries in the right way. Of course, you can’t install the batteries in any way and expect your thermostat to function.

Ensure that the batteries are installed correctly. Take caution not to mix up the negatives and positive ends of the batteries. This could affect how your thermostat functions, resulting in not being able to adjust the temperature properly.

How to fix: replace the batteries correctly

  1. First, put off the power to your thermostat. Then, open the battery compartment to remove the old batteries.
  2. Next, insert two new alkaline batteries in the compartment with the correct polarity. Once you open the compartment, you will see markings showing how the batteries should face.
  3. Ensure to install the batteries in the right position. The markings inside the battery compartment can help you orient the batteries with the right polarity.
  4. Ensure to insert the new pair of batteries correctly so that they have a strong connection.
  5. Double check the battery compartment and confirm that you’ve installed the batteries in the correct orientation.
  6. Consult your thermostat’s manual for further help regarding how to install batteries correctly.

Reason 4: Circuit breaker tripled

If your thermostat fails to turn on after replacing the batteries, sometimes the cause of the problem could be the circuit breaker of your HVAC system.

An electric overload or power outage can cause the circuit breaker to trip off. So when your Honeywell thermostat can’t turn on, check whether the circuit breaker tripped.

The circuit breaker helps to protect your home from power surges. If a circuit breaker turns off, this would cause your thermostat to stop functioning. It trips to minimize the electrical load on the circuit. However, over time some circuit breakers may trip due to wear and tear.

How to check: reboot the HVAC circuit breaker

A tripped circuit breaker or blown fuse could be the reason behind your thermostat not functioning.

Check if the circuit breaker for your HVAC system is on. If the circuit breaker is tripped, reset it and see if the thermostat starts working again.

Also check fuses in the air conditioning unit. If a fuse is blown, replace it with the appropriate type to prevent further problems.

If you begin noticing signs of deterioration around the circuit breaker, or experiencing regular circuit outages or detect a burning odor, call a HVAC professional immediately for help.

Ignoring electrical problems can cause fire and other hazards in your home. Keep the circuit breaker off until the HVAC professional investigates and resolves the problem.

Reason 5: Corrosion in your battery terminals could be the problem

The batteries can corrode the battery terminals. As a result, this can cause your thermostat to stop turning on. Corrosion may prevent current from passing through the batteries to the thermostat.

Corrosion from leaking the batteries can prevent the contacts between the batteries and the thermostat from working properly. Corrosion may occur if you delayed replacing the old batteries, or the batteries had poor seals and, as a result, leaked acid.

Don’t be shocked if you remove the alkaline batteries from your thermostat and notice some corrosion around your battery terminals. Corrosion is a normal part of battery life. Wear and tear is typically the cause of this problem.

You should not ignore the impact of corrosion on the thermostat batteries. Corroded battery terminals are a common cause of decreased lifespan of your batteries and electrical problems in thermostats.

How to fix: clean battery terminals

After disposing the old batteries, check the battery terminals in your thermostat and clean them.

  1. To clean your thermostat’s battery terminals, use a paper towel to wipe away corroded parts.
  2. Use a cotton swab dipped in vinegar or lemon juice to gently rub gently the battery terminals to remove any corrosion.

If this solution doesn’t help resolve your thermostat’s functionality problem, move to the next step.

Reason 6: Glitches and bugs in thermostat

If your thermostat is not turning on even after trying the above tips, technical glitches and bugs could be the cause of the problem.

There are several cases when resetting your thermostat is justified. Technical glitches and software bugs can make your thermostat stuck. Resetting your device can assist fixing these issues. Your thermostat may stop working properly because of faulty controls, a glitch, or is out of sync with your HVAC system.

Also, when you recently changed the batteries of your thermostat, but the device is still not functioning, the reset is recommended.

How to fix: conduct factory reset

  1. First, conduct a soft reset of your Honeywell thermostat to resolve power outage and connection issues or a frozen or stuck thermostat.
  2. If the functionality problem persists after the soft reset, perform a factory hard reset to clear out technical glitches, software bugs, and programming issues.
  3. Follow the thermostat’s manual book when conducting soft reset as well as factory reset.
  4. After the reset, reboot the device.
  5. If the reset doesn’t address the problem, it means the issue your thermostat is facing beyond your control. It would be safer to get a professional in.

My Final Thoughts

Sometimes, the simple maintenance task of replacing your Honeywell thermostat’s batteries can cause problems.

However, with the troubleshooting solutions explained above, you now can resolve the problem of your thermostat not turning on after changing the batteries.

If your thermostat doesn’t function after trying all the above, contact Honeywell support technicians or a certified HVAC professional to get your thermostat addressed.

Brady Klinger-Meyers is an experienced writer and marketer with who currently writes for Robodens as well as other popular sites like MakeUseOf and Techzillo. At Robodens, he focuses on general smart home advice with his interest being accessories and gadgets. Read our Editorial Guidelines and Fact Checking process.


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