The system runs but blows cold or lukewarm air
Rooms never reach the thermostat setting
Heat is uneven from room to room
➡️ Often points to burner issues, heat exchanger problems, or airflow restrictions.
System shuts down before fully heating the home
Thermostat constantly clicks on and off
➡️ Can indicate overheating, dirty filters, thermostat issues, or failing components.
Banging or booming when the heater starts
Squealing or grinding sounds
Rattling or vibrating during operation
➡️ These noises often signal loose parts, ignition issues, blower motor problems, or duct expansion.
Burning smell that doesn’t go away
Musty or moldy odor from vents
Rotten egg or sulfur smell (very serious)
➡️ Persistent smells can indicate electrical issues, dirty components, or potential gas leaks.
Pilot light won’t stay lit
Flame is yellow instead of blue
➡️ Can indicate ventilation problems, dirty burners, or gas supply issues.
Carbon monoxide detector alarms
Soot buildup near furnace or vents
➡️ This is an emergency. Shut off the system and call a professional immediately.
