Why Is My Furnace Not Turning On? Troubleshooting Guide
When temperatures drop in De Pere and Green Bay, a furnace that won’t kick on is more than just an inconvenience, it’s a major concern for any homeowner. If you’ve ever asked, “Why is my furnace not turning on?”, you’re not alone. From minor issues to serious malfunctions, there are a number of reasons a furnace may fail to start.
The good news? Some of the most common furnace issues are easy to identify and even fix with a few basic troubleshooting steps. In this guide, we’ll walk you through common causes, quick checks, and when it’s time to call in a professional, like the trusted team at Richards Heating & Cooling.
Common Reasons Why Your Furnace Is Not Turning On
Several issues could be behind your furnace not working as expected. Here are a few common culprits:
Power supply problems: A tripped circuit breaker or disconnected power switch can prevent the furnace from running. This is often overlooked but easy to check.
Thermostat malfunctions: If your thermostat isn’t set correctly or has dead batteries, it may not be sending the proper signals to your furnace.
Dirty or clogged air filters: Air filters that are overdue for replacement can restrict airflow, causing the system to overheat and shut down as a safety precaution.
Blocked vents or registers: When airflow is obstructed, your furnace can’t circulate heat properly, potentially leading to shutdowns or poor performance.
Dirty burners or flame sensors: Build-up can prevent ignition and keep your system from turning on entirely.
Furnace Not Working? Here’s What to Check First
Before assuming the worst, try these simple troubleshooting steps:
Check the thermostat: Make sure it’s set to “heat” and the temperature is higher than the current room temperature. Replace batteries if needed.
Inspect the circuit breaker: Your furnace’s breaker may have tripped. If so, reset it and monitor the system to see if the issue persists.
Look at the furnace switch: This switch looks like a light switch and is usually located on or near the unit. Make sure it’s in the “on” position.
Replace the air filter: A dirty filter can trigger safety shutoffs. Swap it out with a clean one and see if that helps.
Open all vents and registers: Make sure furniture or rugs aren’t covering heat registers and that all vents are fully open for proper airflow.
Furnace Troubleshooting Tips for Quick Fixes
Some minor issues can be resolved with a quick fix if you know where to look:
Reset the furnace: Many furnaces have a reset button. Turn the unit off, wait a few minutes, then turn it back on and press the reset button if available.
Inspect the blower motor: If it’s humming but not moving air, the motor may be stuck or need servicing.
Clear debris and dust: Dust and dirt on sensors, igniters, or burners can prevent ignition. While some surface-level cleaning can help, deeper maintenance should be left to a professional.
Gas Furnace Not Igniting? Here’s Why
If you have a gas furnace and it's not igniting, a few key issues could be to blame:
Igniter failure: Newer furnaces use electronic igniters that can wear out over time.
Gas supply issues: If there’s an issue with your home’s gas supply or a closed valve, the furnace won’t ignite.
Faulty flame sensor: This small component ensures the burners stay lit. If it’s dirty or malfunctioning, the system may shut down.
These problems often require a trained eye and should be addressed by a licensed technician to avoid safety risks.
When to Call the Professionals
Not all furnace problems can, or should be solved on your own. Contact a professional HVAC technician if you notice:
Unusual noises like banging, grinding, or rattling
Frequent on-off cycling (short cycling)
A persistent burning smell or gas odor
Cold air blowing when the furnace is running
Repeated system shutdowns
A trained technician can accurately diagnose the problem and make the necessary repairs to restore safe and efficient heating in your home.
Get Your Furnace Working with Richards Heating and Cooling
If your furnace isn’t turning on and basic troubleshooting hasn’t solved the problem, Richards Heating & Cooling is here to help. As a trusted local HVAC provider in De Pere and Green Bay, WI, we specialize in fast, reliable furnace repairs backed by transparent pricing and trusted advice.
Whether it’s a simple fix or a more involved repair, we’ll get your home warm again—quickly and professionally.
Call us today to schedule your furnace repair or maintenance service and stay comfortable all season long.
