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Clearing 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 failure, your system will not function for safety reasons.

Trust the Experts at Service Experts Heating, Air Conditioning & Plumbing to deal with fixing this furnace error. Our ACE-certified technicians are among the best in the industry when it comes to recognizing and repairing furnace problems.

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 operation.

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

  • Your furnace’s control board begins the draft inducer blower motor. This gets rid of combustion gases from the heat exchanger and sucks in new gas and air so the burners can start.
  • When the pressure switch senses that a suitable amount of air is being pulled into the burners, it closes and tells the control board to ignite the furnace.
  • Your furnace ignites and heats your space.

A two-stage furnace has more than one pressure switches, which help it to run at multiple speeds—and use energy more efficiently.

What Happens When a Low Pressure Switch Malfunctions

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

There could be a:

  • Closed off vent
  • Clogged condensate drain
  • Cracked hose

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

Your furnace will show 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 notice fast flashes or an alternating slow flash as it replays a fault code.

Estimated Repair Cost for Furnace Error Code 223

The expense to fix your furnace depends on the root problem48} and how long it takes to repair 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 Service Experts Heating, Air Conditioning & Plumbing

When you have to have furnace service, you can call on the professionals at Service Experts Heating, Air Conditioning & Plumbing

to handle the fault code and get your heat working again.

Call us at or schedule an appointment online today.

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