Appliance guides

Furnaces troubleshooting

Start with safe checks when your furnace has a problem.

• How to Clean a Furnace Flame Sensor Safely
• Furnace Not Working: Read the Blinking Light Code
• Furnace Blowing Cold Air Instead of Hot: Causes
• Furnace Fan Not Working: Capacitor, Motor, Limit Switch
• Furnace Making Noise: Bang, Squeal or Rattle
• Furnace Not Igniting: Flame Sensor and Igniter
• Furnace Not Turning On: Step-by-Step Checks
• Furnace Repair or Replace? Cost by Age and Problem
• Furnace Short Cycling: Causes and Fixes