Why does my furnace say lockout?

What does ignition lockout fault mean? When a sensor detects an unsafe condition, the furnace controller will shut off the power and fuel to prevent hazards. This is known as an ignition lockout, a condition that can be caused by a number of different sensors found in your furnace.

What causes a furnace controller to lock out?

Here are the most common lockout culprits explained. Defective flame sensors are one of the most common causes of lockouts. When your furnace begins to start, the sensor checks for the presence of fire. If the sensor is faulty or dirty, it won’t be able to detect the flame and the controller will stop the ignition sequence.

What should I do after resetting my furnace lockout?

In fact, most annual furnace inspections involve a technician cleaning the flame sensor as part of the preventative service visit. A furnace that cycles on and off quickly, especially after resetting a lockout, often has a dirty flame sensor.

What kind of lockout does a furnace have?

There are two main types of furnace lockouts you should know about – a hard and a soft lockout. As we’ve already explained, your furnace controller will stop the ignition sequence and prevent unsafe operation if the sensor doesn’t detect the flame within a set time period.

How to fix a furnace that is not igniting?

1 Turn off power to the furnace. 2 Take off the furnace door, and locate the igniter. 3 Remove the two screws holding it in place, and gently pull it out with or without detaching the wires. 4 Be careful NOT to touch the “stick” part of the igniter. 5 Gently sand all sides until the soot has been removed. …

What causes a furnace to lock out when it tries to start?

A home furnace lock out prevents unsafe operation. Common causes of furnace lock outs are a defective igniter or defective flame sensor. When the furnace attempts to start, sensors check for igniter action and for the presence of flame. If the igniter doesn’t activate within a few seconds, the furnace controller stops the ignition sequence.

What does it mean when your furnace won’t start?

Finally, make sure the gas supply to the furnace is open. If your furnace clicks on or initiates the start cycle, but does not fire up, you likely have a faulty or dirty ignitor/sensor. This is one of the most common furnace problems.

In fact, most annual furnace inspections involve a technician cleaning the flame sensor as part of the preventative service visit. A furnace that cycles on and off quickly, especially after resetting a lockout, often has a dirty flame sensor.

What to do if your furnace ignitor does not start?

If your fuse is OK, tape your door safety switch shut so you can view the status LED light on the control board with the furnace power on. Please remember to turn the power back off before touching anything inside the furnace. I do not want to hear of anyone getting hurt or shocked!