Fixing Error Code 223 on Your Lennox® Furnace

Getting cold because you’re getting error code 223 from your Lennox® furnace?

This is telling you your furnace’s low pressure switch is open. Due to the issue, your system will not work for your safety.

Trust the Experts at Stallion Heating and Air Conditioning to deal with fixing this furnace error. Our ACE-certified technicians are among the brightest in the industry when it comes to diagnosing and repairing furnace issues.

Your satisfaction is critical to us. That’s why we back our furnace repair* for a year.

How a Low Pressure Switch Works

Pressure switches are an essential part of the heating process.

Here’s how your furnace works after the thermostat begins to call for heat:

  • Your furnace’s control board begins the draft inducer blower motor. This exhausts combustion gases from the heat exchanger and sucks in new gas and air so the burners can start.
  • When the pressure switch senses that enough air is being pulled into the burners, it closes and triggers the control board to ignite the furnace.
  • Your furnace ignites and heats your home.

A two-stage furnace has more than one pressure switches, which allow it to run at different speeds—and use less energy.

What Happens When a Low Pressure Switch Fails

The low pressure switch may be open for a variety reasons.

There could be a:

  • Closed off vent
  • Plugged condensate drain
  • Cracked hose

There could also be an issue with the switch itself, the inducer or the circuit board.

Your furnace will tell you there’s an issue with a red flash from its indicator light, which it uses to exhibit error codes. It has this red light to flash code, like Morse code.

You might observe fast flashes or an alternating slow flash as it repeats a fault code.

Estimated Repair Cost for Furnace Error Code 223

The expense to fix your furnace depends on the root problem48} and the hours it takes to remedy it.

Here are the usual replacement costs for several components that could be affected:

  • Pressure switch—$40 to $350
  • Inducer—$600 to $1,500
  • Circuit board—$200 to $600

Call the Experts at Stallion Heating and Air Conditioning

When you require furnace service, you can lean on the professionals at Stallion Heating and Air Conditioning

to take care of the fault code and get your heat moving again.

Call us at or schedule an appointment online today.

  • Zoning Systems: Customized Comfort in Every Room

    Central heating and cooling systems have revolutionized home comfort and made it possible to stay completely comfortable in any season or climate. However, while centralized systems are a handy way to manage the temperature, they occasionally fall short when it comes to evenly distributing heated... Continue reading

  • Eight Popular Heating Myths Debunked

    There are lots of myths out there about home heating that lead to confusion and inefficient furnace usage. It’s time to set the record straight. Here, the heating authorities at Service Experts Heating, Air Conditioning & Plumbing debunk the eight most common myths to keep your home... Continue reading

  • Eight Ways to Upgrade Your HVAC System

    During the cold winter months in the U.S., there’s no better way to improve your home’s comfort than with a few effective upgrades. It’s not only about keeping the house toasty warm as the snow begins to fall—it’s about enhancing efficiency and removing pollutants from the very air you... Continue reading