How To Reset the Furnace Control Board in 5 Steps

Using your furnace in unsafe conditions may force it to shut down completely, otherwise known as a furnace lockout. You may experience either a soft or hard lockout. A hard lockout requires you to know how to reset the furnace control board. 

Soft lockouts happen when one of your furnace sensors detects an issue. During a soft lockout, the furnace sits idle until the lockout period ends, after which it tries to start up automatically. Hard lockouts occur after several recurring soft lockouts.

A hard lockout typically points to a severe issue that will prevent the furnace from restarting until you reset the control board. As the top contractor for Boiler Springs heating and air conditioning, our crew at Smooth Sailing Heating & Cooling highlights how to reset the furnace control board.

How To Reset Your Furnace Control Board 

Situations that may warrant a furnace reset include closed gas valves, flame sensor issues, or overheating. Establish why your furnace locked out in the first place and address the issue to prevent a recurrent lockout.

It also helps to note that the type of furnace will determine the steps you take when resetting a furnace control board. 

1. Check for Error Codes

Error codes help pinpoint the cause of the problem more quickly and accurately. Start by locating the control board’s diagnostic light. You’ll typically find an LED light that flashes a series of codes to indicate the specific issue. 

Check the furnace’s manual or error code chart for a list of potential error codes and their respective meanings.

2. Turn the Power Off

Once you address the issue based on the error code, turn your furnace’s power off. Simply locate the toggle switch, which resembles a standard light switch, and flip it to turn your furnace off.

If your furnace doesn’t have a toggle switch or you can’t locate it, find the circuit breaker connected to your furnace and switch it off. Check the diagnostic light once more and confirm that it stays off.

3. Locate the Reset Button 

Knowing how to reset the furnace control board requires you to find the reset button. However, not all furnaces have a reset button. If your electric furnace has one, you’ll most likely find it next to the motor, located within the blower housing.

If you own a gas furnace, you’ll probably find it in the control panel. An oil furnace will usually have its reset button somewhere in the blower compartment. Check the manufacturer’s manual for specifics. 

Remember that you should only press the reset button after identifying the underlying cause of the furnace malfunction. Once you find the reset button and confirm that the furnace has no power, simply press and hold the reset button for a few seconds.

The duration may vary from one furnace to another, so refer to the manual for precise instructions. After holding the reset button for the appropriate time, release it and wait for the furnace to respond. Give the system a few moments to complete the reset process. 

4. Wait for the Furnace To Reset 

The waiting period after resetting allows the furnace’s control board to clear any faults or error codes and re-establish normal operation. The reset process varies depending on the furnace make and model and could take anywhere from 30 seconds to a few minutes to complete. 

As the furnace resets, you may hear relays clicking or the blower fan starting and stopping or see lights blinking. Once the reset duration passes, check if the furnace has reset successfully. 

It should have stopped displaying error codes or fault indicators, and the control board should be ready to resume normal operation. 

5. Switch on the Furnace and Test It 

After the furnace resets, turn on the power to your furnace. Restoring the power supply allows the furnace to work as it normally would.

If the furnace doesn’t respond or shows signs of continued issues after turning on the power, refer to the manual or contact an expert for further diagnosis. Older furnaces may not fire up until you relight the pilot gas light.

Trust Smooth Sailing Heating & Cooling for Your Comfort Needs 

Is your home furnace experiencing issues? Count on us to troubleshoot, diagnose, and restore your comfort as soon as possible. Fortunately, knowing how to reset the furnace control board can help limit the frustrations of a locked-out unit.

Call Smooth Sailing Heating & Cooling at (864) 531-7732 for quality heating and cooling services in Boiling Springs, SC. Reach out for expert furnace repair or tips on adding zones to your HVAC system.