Discovering that your furnace won’t kick on when the house is freezing is like finding out your umbrella’s broken during a downpour.
Annoying? Yes. But often, the fix is simpler than you’d expect.
Before you call in a pro, try troubleshooting these common furnace issues on your own. If your furnace still won’t turn on after trying troubleshooting tips, it’s time to call the professionals.
Key Takeaways
- Check to see if your thermostat is set to heating.
- Power problems could be behind your furnace issue—check your circuit breaker.
- Gas supply problems may be causing a lack of heat.
- The pilot light or ignition sensor might need some TLC.
- Dirt buildup on furnace burners could the issue.
Determine What Type of Furnace You Have
Most homes are equipped with forced-air gas furnaces. This type of furnace heats air, which is then blown through your home’s duct system.
It’s the most common setup, but your troubleshooting steps might vary if you have a different type of furnace, like an electric model.
Knowing your furnace type helps you tackle problems in the right way, so double-check if you’re unsure.
Reasons Why Your Furnace Won’t Turn On
When your furnace refuses to turn on, it’s usually due to one of a few common issues. Here’s a breakdown of the most frequent causes and how you can potentially fix them yourself.
Faulty Thermostat
First things first, check your thermostat. It sounds obvious, but you’d be surprised how often this simple step is overlooked.
Make sure it’s set to “heat” and the room temperature is below the set temperature. You can also try switching the fan to “on.” If your thermostat runs on batteries, swap them out, just in case.
If you’ve got a digital or programmable thermostat, a power outage might have caused the settings to reset. This can throw off your heating schedule, and your furnace won’t get the memo that it’s supposed to turn on.
If you’re still in the cold after these quick fixes, it could mean the thermostat itself is faulty, and you might need to replace it.
Tripped Circuit Breaker or Blown Fuse
Even gas furnaces need electricity to run the furnace blower motor and ignition system. If your furnace won’t turn on at all, head over to your circuit breaker panel. Look for a tripped breaker—if you find one, flip it back into place. If it trips again, that could indicate a bigger electrical problem.
For homes with fuses instead of breakers, check for blown fuses and replace them. But if the new fuse blows right away, you’ll need an HVAC technician to figure out what’s going on.
Gas Line Issues
Sometimes the issue isn’t with the furnace at all it’s with the gas supply. Make sure the gas valve outside is open. An easy way to check if gas is flowing properly is by testing another gas appliance, like your stove. If that’s working, the issue may lie with the furnace’s gas supply.
Safety tip: If you catch a whiff of rotten eggs, that could mean a gas leak. In that case, don’t mess around—evacuate the house immediately and call your gas company or 911. Gas leaks are nothing to play with.
Faulty Ignition Sensor or Pilot Light
If you hear a clicking noise but no heat, your furnace’s ignition system might be to blame. Gas furnaces with older systems use pilot lights to ignite the burners, while newer models typically have electronic ignition sensors. Over time, these sensors can get dirty or fail entirely.
A simple cleaning can sometimes fix the problem, but if you’re not comfortable doing it yourself, a technician can handle it. With longer gas lines, you might notice a delay between turning on the furnace and the pilot lighting. This is normal, but if it takes longer than a minute, it might be time to get the ignition system checked out.
Dirty Burners
Burners covered in dirt and grime can block the gas flow, preventing your furnace from igniting. You might notice your furnace kicking on but then shutting off before the house is heated. This could mean that dirty burners are causing inefficient heating. A yearly inspection and cleaning by a pro can help prevent this from happening in the first place.
Dirty burners may not shut down your furnace, but they can lower its efficiency. This can raise your heating bills and leave you feeling cold.
Troubleshooting Why Your Furnace Won’t Turn On
Before you grab the phone to call for backup, there are a few simple checks you can do yourself. They won’t take long, and they could save you the cost of a service call.
- Check your thermostat: Make sure it’s in heating mode and the temperature is set correctly.
- Check your circuit breakers: If any are tripped, reset them.
- Check your gas supply: Test other gas appliances to verify gas is flowing.
- Check the pilot light: If it’s out, follow the service panel instructions to relight it.
- Check the drain pan: A full drain pan can trigger a safety switch, so make sure it’s draining properly.
Trust the Professionals at Mister Greenway Nashville for Furnace Repairs
Sometimes, troubleshooting can only take you so far. If your furnace still won’t turn on, or you’ve run into issues that seem complicated—especially when gas or electricity is involved—don’t hesitate to call a professional. At Mister Greenway, we’ll scramble a trained tech on their way in under 30 minutes!
Whether it’s a faulty ignition sensor, a gas leak, or an electrical issue, our pros have the tools and expertise to get your furnace up and running again. Plus, regular maintenance can help prevent these issues from popping up when you least expect them.
FAQs
If your furnace won’t turn on, you’re not alone. Many homeowners face the same issues every winter. Here’s a quick FAQ guide to help you troubleshoot your furnace woes:
Why is my furnace making a clicking noise but not turning on?
A clicking noise usually means there’s an issue with the ignition sensor or the pilot light. It’s trying to ignite but failing. Cleaning or replacing the ignition sensor might solve the problem.
How often should I change my furnace’s air filter?
Every 1-3 months is a good rule of thumb. A dirty air filter can restrict airflow and cause your furnace to overheat, which might prevent it from turning on.
What should I do if I smell gas near my furnace?
Evacuate your home immediately and call your gas company or emergency services. Gas leaks are extremely dangerous and need to be handled by professionals.
Why is my furnace blowing cold air?
This could be caused by several things: a faulty thermostat, a dirty filter, or even an issue with the pilot light. Check those components first, and if you’re still getting cold air, call a technician.
Can I troubleshoot furnace issues on my own?
Simple fixes, like resetting a circuit breaker or changing the thermostat batteries, are safe for homeowners to try. For gas or electrical issues, it’s best to call in a professional.
Final Thoughts
Your furnace not turning on can be a headache, but it’s often something you can fix yourself. Checking the thermostat, gas supply, and circuit breakers might just get the heat back on without much hassle.
But remember, if any of the troubleshooting steps seem dangerous or you’re unsure, call a professional. A well-maintained furnace is key to keeping your home warm and safe all winter long.
