Demonstrating HVAC Expertise

« Back to Home

Time For A Change -- For Your Thermostat Batteries

Posted on

When was the last time you changed your HVAC thermostat's batteries. If you can't remember, you're not alone. Most homeowners tend to forget about their battery-powered thermostats, only to be reminded when their thermostats suddenly stop working. The following offers a few tips on how to check and change your thermostat's batteries.

Why You Should Change Your Batteries

You'd think your thermostat could simply use your home's main power. In fact, many thermostats do rely on main power, but there's a good reason why the vast majority of them are battery-powered. Being on battery power helps the thermostat retain its programmed settings in the event of a power outage.

But even the best batteries can't last forever. Depending on the type of battery your thermostat uses, you can expect anywhere from 2 to 5 years of life before they need changing. Some applications can drain battery life in as little as a few months.

When to Change the Batteries

It's a good idea to check your thermostat's batteries as part of your annual HVAC system inspection. You can even proactively change the batteries during this time to avoid any unwanted surprises. But there are other times when you'll want to change the battery:

  • When the display shows a "low battery" indicator. This is usually a sign that your batteries are on their last legs. Most warnings appear about a month before your batteries are completely discharged.
  • When the display goes completely blank. At this point, the batteries are completely dead, and so are your HVAC controls. You should replace the battery ASAP to restore your HVAC system's functions.
  • When you see visible corrosion on or near the battery. Visible corrosion could be a sign of a leaking or otherwise faulty battery. Use a cotton swab soaked in vinegar to clean up the terminals and replace the batteries with a fresh set.

How to Replace the Batteries

Compared to some of the other maintenance tasks for your HVAC system, changing your thermostat's batteries is relatively easy. Simply remove the thermostat from its wall mount, locate and remove the external battery cover, and replace the batteries before remounting the thermostat.

On some thermostats, you'll need to remove the faceplate instead of dismounting the entire thermostat. Watch for any screws that need to be loosened before removing the face. After gently pulling the faceplate away from the thermostat, locate and replace the batteries before remounting the faceplate.

For more information or help, contact local air conditioning services