Winter in Tennessee can catch residents off guard, especially when warmer areas like Cookeville and Nashville drop into below-freezing temperatures. What’s worse is if your furnace doesn’t turn on. It’s easy to panic during a moment like this, and we don’t blame you if you do. But try not to worry.
You may be asking, “Why is this happening now? My furnace was working before!” There are many reasons why a reliable heating system like your furnace could end up non-functional. Let’s explore the common causes behind this problem and ways you can troubleshoot.
Common Reasons Why Your Furnace Won’t Ignite or Turn On
Furnaces can fall prey to common problems, many of which can cause your system to malfunction. If your furnace won’t turn on, it could have issues such as:
- Flame Sensor is Dirty
The flame sensor is what detects your pilot light to start the heating process. When the sensor is dirty, it won’t be able to detect if the pilot light is lit, shutting off the furnace. Luckily, a dirty sensor doesn’t need a full replacement. Just a thorough professional cleaning. Before you start grabbing your supplies, the sensor is a sensitive component and not easy to access, so it’s best to leave it to the pros.
- Power Switch is Off
Flipping your power off is an accident that can occur at times. Take a look at your switch—is it on or off? If it’s off, switch it back to on to see if that restores functionality. If your switch is switching off automatically, you’ll need a professional inspection to find out the cause.
- Dirty or Clogged Furnace Filters
If your filters are clogged, air won’t be able to circulate. The best way to prevent clogged filters is by scheduling a routine system cleaning from a professional who will help clear out blockages.
- Blocked Ignition Exhaust
Ignition exhaust is vital to normal operation. It prevents any combustible gases from back-drafting. When the exhaust is blocked, the flow of air is cut off and ignition is no longer possible. Unless cleaned out, the exhaust risks reducing the efficiency of your system, eventually leading to a complete breakdown.
- Failed Capacitor
This is an essential part of assisting your blower motor. When it fails, your blower motor can’t run and your furnace won’t be able to turn on. The best way to test your capacitor is a professional maintenance check and a replacement if needed.
- Blower Motor Malfunction
Your blower motor is integral for the air circulation throughout the furnace. When the motor malfunctions and air stays stagnant, your furnace follows suit. This problem will most likely need a professional replacement or repair to get your furnace up and running.
- Faulty Control Board
This handy component helps monitor the furnace temperature and adjusts it accordingly. If the board malfunctions, your furnace may run for a short period before shutting off. Call for professional assistance to get your furnace back up and running again.
- Safety Features Are Triggered
Your furnace comes equipped with plenty of safety features that could be stopping your furnace from turning on. Your furnace may have tripped the:
- Pressure Switch: This switch flips when it detects gasses that have not been fully exhausted from your home. It stops functioning since the flue gasses could spark from the negative pressure created by the ignition process.
- Safety Float Switch: This checks the amount of condensation in your HVAC’s drain pan, turning the system off when that pan becomes too full.
- Flame Roll-Out Switch: If flames somehow escape through the combustion chamber, the flame roll-out switch shuts off the system before the fire spreads.
- High-Limit Switch: This switch works with your thermostat to maintain your temperature setting. It will shut off your system if the furnace gets close to overheating.
If issues continue, it’s best to contact a furnace professional to conduct an in-depth assessment of your system.
DIY Troubleshooting Tips When Your Furnace Won’t Turn On
Some furnace issues can be fixed at home. If you are ready to pull up your sleeves, here is what you can do:
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Check Your Circuit Breaker
Check your breaker box to see if it was flipped recently. If the breaker is in the “off” position, go ahead and flip it back to “on” and see if it gets your furnace running again. If the furnace is constantly tripping the breaker, it indicates an electrical issue with your system.
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Check Your Thermostat
A simple check of your thermostat could make the difference. Inspect your thermostat is set to the heating mode and, above all, make sure it is turned on. While it sounds simple, accidents can happen. It would also be wise to check if your thermostat uses a scheduling program to see if that is causing any issues. And finally, make sure to switch out those batteries if your thermostat has been using the same ones for a while.
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Check Your Furnace Filter
This filter is typically located in the blower compartment and clears the airflow of your furnace. When dirty or clogged, airflow is restricted and your furnace won’t be able to kick on or circulate air. A simple change to a clean filter normally helps restore functionality, but if not, it might be time to call for professional help.
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Check The Pilot Light
Always check to make sure your pilot light is lit. Your furnace comes with a small see-through panel to check the light. If you see no flame, there could be a problem with the gas supply, and as a result, the furnace won’t turn on. When your pilot light won’t turn on or stay lit, call for a professional to assist you.
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Check the Exhaust Vent
Check and clear out anything that may be blocking out the exhaust pipe. Blockages stop your furnace’s exhaust from having a place to go, which the system in response stops operating.
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Check the Furnace Access Panel
Also known as the furnace door, this component must be secured and closed for your system to start running. Modern gas furnace systems have a safety switch that stops all functions if the panel is not closed properly. If you have had maintenance or an inspection recently, check the panel just in case it was accidentally left open.
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Check the Furnace Power Switch
As the name suggests, this switch controls the overall power of the furnace unit. Go ahead and locate your unit’s switch, typically on the side or on a nearby wall, and make sure it is flipped on. If flipping it back on does not restore consistent functionality, it’s time for a professional to help you out.
When Should You Call an HVAC Technician to Repair Your Furnace?
If you are still stuck with a stubborn furnace that won’t turn on, it’s time to call an HVAC technician. An expert technician will provide a full assessment of your system and perform routine maintenance checks. If the problem is much more severe, the technician will provide suitable repair solutions for your unit.
Ensure Reliable Heating This Winter With Expert Furnace Solutions in Cookeville, TN & the Metro Nashville Area
Your furnace can fall prey to a wide range of issues, from dirty filters, and broken motors to something as simple as being set to “off”. If you have done all you can by yourself, turn to the technicians at Charles Stones.
Our heating services provide an in-depth inspection of your system along with any repairs or maintenance needed. We are equipped to take on all types of furnaces including gas or electric. Have an emergency? Give us a call.
If you are in the Upper Cumberland region or the Metro Nashville area, our expert HVAC technicians are ready to assist you with professional furnace repair and maintenance services.
