Why is your furnace not heating the house?
A furnace that runs without warming the home can have several causes. You can check its settings and describe the symptoms without opening or repairing the equipment.
Check the thermostat settings
Confirm that the thermostat is calling for heat and review any schedule. The fan setting and the heating mode are different controls; “Auto” can be a valid fan or system setting, depending on the thermostat. Follow its manual. Replace owner-serviceable batteries only as directed.
Look for airflow changes
Check an accessible filter using the equipment instructions. Keep room registers and return grilles clear. Uneven room temperatures can involve airflow, controls, building conditions, or equipment faults; they do not prove the furnace needs replacement.
Leave ignition and internal work to a technician
Do not remove service panels, bypass a safety control, work on a gas valve, or try repeated resets. Tell the office about an error message, unusual sound, repeated shutdown, or lack of heat.
If you smell gas, leave the area and call 911 from a safe place outside. Do not operate switches or try to find the leak. See PG&E’s gas-safety instructions.
Arrange the right visit
A repair diagnosis has a visit charge. Read what a repair visit costs for the first-hour charge, additional time, parts, after-hours rates, and travel charges. The technician explains repair options and costs before you approve repair work.
The office confirms the appointment. A repair can require parts or further work after diagnosis. If replacement is one option, ask the technician to explain both the repair and replacement scope before you decide.
For planned care, see ENERGY STAR’s maintenance checklist.
