No heat? Start with the safe, observable basics.

Immediate safety

Leave the building when the condition may be dangerous.

If you smell gas, suspect carbon monoxide, see smoke or fire, hear an active electrical arcing sound, or a carbon-monoxide alarm sounds, move people and pets outside and contact the appropriate emergency or utility service. Do not stay inside to troubleshoot.

Safe checks

Confirm settings and visible conditions without defeating protections.

If there is no immediate hazard and you can do so safely, record what the system is doing before changing anything. The sequence and timing often help diagnosis.

• Confirm the thermostat is in heating mode and set above room temperature
• Replace thermostat batteries if the display indicates they are low
• Confirm the furnace switch and circuit breaker are on; do not repeatedly reset a tripping breaker
• Check whether the filter is heavily loaded or installed incorrectly
• Note whether the blower, inducer, or burner starts and how long it runs
• Photograph any visible fault code without removing secured panels
• Check whether other propane or gas appliances operate only if that can be done normally and safely

For the service call

Send observations, not a self-diagnosed part request.

Share the property address, indoor temperature, thermostat display, equipment type and age if known, fuel, what starts or does not start, timing, recent service, filter condition, fault code, and unusual noise or odor. Those observations are more useful than guessing which component failed.