Vertex Mechanical’s HVAC, Plumbing & Electrical Blog


What Does My Thermostat Error Code Mean?

Thermostat error codes are the HVAC system equivalent of a check engine light. These codes indicate one of hundreds of issues with your HAVC unit, the thermostat itself, or the connection between the two. Most thermostat error codes are a puzzling mix of letters and numbers — but with the right information, it’s a blueprint of how to fix your system.

Since the hot summer season leads to heavy air conditioning use, you’re more likely to see a thermostat error code this time of year. If you go to crank your AC on a hot summer day and get a thermostat error code in response, give us a call or get to work fixing it yourself. While savvy homeowners can investigate their thermostat error codes, most people choose to bring us in to take a look.

Learn more about the most common reasons for thermostat error codes — and check out the Nest and Honeywell thermostat error code listings.

Most Common Thermostat Error Codes

Only digital or wi-fi thermostats have the ability to throw error codes when encountering an issue — old analog thermostats aren’t sophisticated enough. If your analog thermostat has an issue, it will likely just result in a no-AC emergency.

While in theory, you may be able to fix your own thermostat, most homeowners simply call their trusted HVAC contractor. Here are the most common reasons for a thermostat failure or error code:

  • The wiring between the air conditioning or heating unit is loose or entirely disconnected.
  • The breaker that provides power to the unit is turned off or tripped.
  • The thermostat is unable to connect to your wireless network or to the internet itself.
  • The thermostat doesn’t support the air conditioner fan type.

Our expert air conditioning technicians check your thermostat during our comprehensive tuneup. Learn more about our extensive tuneup.

Nest and Honeywell Thermostat Error Codes

Nest and Honeywell are two of the largest thermostat manufacturers for houses in the United States. Both Nest and Honeywell maintain databases of their thermostats and make them available online to consumers.

Check out the Nest thermostat error code database.

Check out the Honeywell thermostat error code list.

While this manufacturer information is as user-friendly as possible, it can still be difficult to understand — and even more difficult to put into action. As a full-service heating and cooling contractor, we can help you fix your thermostat error code.

Upgrade to a Programmable or Wi-Fi Thermostat

wi-fi thermostat

If you still use an outdated analog thermostat, you’re missing out on the convenience and savings of a 21st century upgrade. Not only are digital thermostats easier to use, but they also have a host of benefits. Here are the two most popular types:

  • Programmable thermostats — These digital thermostats save you money by allowing you to program the thermostat to follow your schedule. That way you never pay to heat or cool an empty house while you’re at work.
  • Wi-Fi thermostats — This type of modern thermostat connects to your home’s Wi-Fi, allowing you to control your home temperature from your phone. Again, this high-tech thermostat saves you money by making sure you never pay to heat or cool your home when you don’t need to.
Lancaster and Berks County’s Heating and Cooling Specialists

Whether you need help understanding a cryptic thermostat error code, or you have a full-on dead air conditioning disaster, we’re the team that has your back.

Vertex Mechanical isn’t a chain and our technicians don’t work on commission to upsell you services you don’t need. All we do is provide the expert HVAC repairs and upgrades you want at a price you feel comfortable about. We serve our neighbors in south-central PA, including Lancaster County, Berks County, and more!

Contact Vertex Mechanical for all of your heating and cooling needs.

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