Nest Support

Questions about Nest Learning Thermostat or Nest Protect: Smoke + CO alarm? We've got answers, videos, and plenty of resources to help you out.

Will the Nest Thermostat let me know when I need to change my air filter?

Having a clean air filter is an important part of maintaining your forced air heating and cooling system. Activating your Nest Thermostat's Filter Reminder will help you keep track of when to change it.

Forced air systems, like furnaces, air conditioning and heat pumps, move warm or cool air to your home through ducts and vents. To prevent dust and debris from being blown into your home along with that warm and cold air, your system will have one or maybe more filters.

When filters get clogged with too much dust, they reduce the efficiency of your system and increase heating and cooling costs, since it’s harder for air to move from your heating system into your home. The build-up of hot air behind a very clogged filter can even raise the temperature near your heating system enough to trigger it’s emergency shut-off mechanism, causing your heating system to turn on and off intermittently. Clogged filters can also mean more mold, dust and other allergens in your home.

How do Nest Thermostat's Filter Reminders work?

Other thermostats have filter alerts that go off at set times: once a month, every six months or every year.

The Nest Thermostat uses system runtime to estimate when you need a Filter Reminder. So if you don’t turn cooling on much during the summer, you may go months without a Filter Reminder. If it’s a very cold winter and the heating runs a lot, you’ll get Filter Reminders more often.

Nest will show you a Filter Reminder on the Nest Learning Thermostat.

Note: Filter Reminders are not available on the Web or Mobile apps.

How do I turn on Filter Reminders?

If you’d like for your Nest Thermostat to remind you when your filter needs to be changed, you can enable Filter Reminders in Settings:

  • On your Nest Learning Thermostat, go to SETTINGS > REMINDERS.
  • When asked if you’d like your Nest Thermostat to remind you about your air filter, select Yes.
  • Next, select in what month you last changed your filter. Your Nest Thermostat will use this initial estimate to start measuring filter efficiency.

Note: Filter Reminders are only available for homes that have forced air heating and/or cooling systems.