A furnace that won’t start can be a major inconvenience, especially during the colder months when your home relies on steady, reliable heat. Fortunately, many common furnace issues can be resolved with some basic troubleshooting steps. LV Heating & Cooling will walk you through how to troubleshoot and fix a furnace that won’t start, including simple fixes and identifying when it’s time to call a professional HVAC technician.
Ensure the Furnace Power is On
Before assuming there’s a major problem, make sure the furnace has power. Even gas furnaces rely on electricity for components like the blower and control systems.
• Check the Furnace Switch: Furnaces typically have a power switch located nearby, often on a wall or the furnace itself. Make sure this switch is in the “on” position. It’s easy to accidentally flip this switch off when cleaning or performing other tasks around the furnace.
• Inspect the Circuit Breaker: Check your home’s electrical panel to see if the furnace circuit breaker has tripped. If it has, reset the breaker by flipping it back to the “on” position. If the breaker trips again, there may be an electrical issue with the furnace that requires professional attention.
Check for a Blown Fuse
If your furnace uses a fuse, a blown fuse could prevent the system from starting. Locate the furnace’s fuse box and inspect the fuse. If it’s blown, replace it with a new fuse of the same rating. If the fuse blows again, there may be an underlying electrical issue that needs to be addressed by an HVAC technician.
Inspect the Pilot Light
If you have an older furnace with a standing pilot light, the issue may be that the pilot light has gone out.
• Relight the Pilot Light: Follow the manufacturer’s instructions for relighting the pilot light. This usually involves turning the gas valve to “pilot,” pressing down the reset button, and using a lighter or match to ignite the flame. If the pilot light doesn’t stay lit, there may be a problem with the thermocouple.
• Check for a Yellow or Flickering Flame: The pilot light should burn a steady blue flame. A yellow or flickering flame can indicate incomplete combustion, which may signal a gas issue or dirty burner. If you notice this, turn off the furnace and contact a technician to inspect it.
Check the Electronic Ignition
Newer furnaces use an electronic ignition system rather than a standing pilot light. If the furnace isn’t starting, the igniter may be the culprit.
• Look for Signs of Ignition Failure: If you have a hot surface igniter, it should glow when the furnace tries to start. If it doesn’t glow or you hear a clicking sound without ignition, the igniter may be cracked or faulty.
• Call a Professional for Igniter Replacement: Replacing a hot surface igniter or electronic spark ignition system is a job for a professional. If you suspect ignition issues, it’s best to call an HVAC technician to assess and replace the component.
Central Forced Air Furnace Heating Inspections, Tune Ups, Repair, Replacement & More in Summerlin, North LV, Henderson, Enterprise, Paradise, Spring Valley, Sunrise Manor & Greater Las Vegas, NV
If your furnace won’t start, there are several common issues that can be resolved with simple troubleshooting. Regular maintenance, such as replacing air filters and scheduling annual inspections, can also help prevent future problems. If the issues continue, contact LV Heating & Cooling today.