Sometimes, your furnace limits prohibit you from turning it on again. If this happens, you are likely be facing a hard lockout. But if you have more attempts to turn it on, your furnace is experiencing a soft lockout. The number of attempts will depend on your furnace. But before entering details, you should know why your furnace is locking out.
Common causes of a furnace lockout include:
- Faulty flame sensor
The sensor is essential and helps check the presence of fire when the furnace starts. It’s a safety feature that prevents gas leaks or fires. However, it won’t detect the flame if it is defective, and the controller will end the ignition sequence. You’ll have two more attempts to start the furnace before it becomes locked.
- Defective igniter
An igniter is a vital part of your furnace. It should activate within a few seconds to allow the flame sensor to detect the flame. But if it is faulty, it will take more time before activating, meaning the sensor won’t sense the flame. As a result, the controller will stop your furnace, and after the third attempt, it will go into a lockout state. However, the Furnace Repair Calgary technicians can help replace the igniter and fix other issues with your furnace.
- A faulty induced motor
An induced motor is a motorized fan circling air through the furnace and heating vents. They mostly fail due to aging furnaces or if they become clogged by debris. Diagnosing the problem might require special skills, so don’t hesitate to seek expert help.
- Limit switch response
A limit switch monitors heat exchanger temperatures and fuel pressure. It closes and instructs the furnace to close, leading to a lockout when the temperature or pressure is extreme. A dirty filter or an obstruction in the vents can cause the limit switch to trip as it reduces the airflow.
Best ways to fix a furnace lockout
- Clean or change the flame sensor
Inspect the flame sensor to identify issues such as cracks or other damages. If it contains soot or minor corrosion, thoroughly clean it. Consider replacing the furnace flame sensor if cleaning doesn’t fix the problem.
- Clean the air filters
A clogged air filter reduces the air supply to the system, causing the limit switch. The secret is cleaning it regularly to ensure it’s safe and functioning. You can try to restore the furnace from the lockout after cleaning.
Additionally, clean and inspect the vent pipes. Clear the signs of debris or obstruction inside your vent pipes.
- Check the furnace gas valve
Issues with your furnace gas valve can cause a lockout. To fix this, inspect the gas valve and ensure none of its parts are loose or faulty. Also, check that the furnace has power and hasn’t been accidentally tripped off.
Further, check and fix loose or faulty wiring. Carefully inspect all the parts while identifying the issues and fixing them. If you can’t spot or address the issues, it’s best to contact a professional.
- Seek the help of a pro
If your efforts to fix the furnace lockout fail, it’s best to enlist the help of a professional HVAC technician. The expert will assess the situation and help identify and fix the problem with your furnace.
Final thoughts
Working with a professional furnace repair technician to avoid further damage to your HVAC. Avoid DIY repairs, and schedule regular maintenance by a professional. This way, you can be sure of optimal functioning of your furnace.
