Most Tucson gas furnaces sit from spring until the first cold night. The hot-surface igniter is a common part to fail in that first call for heat. It should glow, then the gas valve should open, then the flame sensor should prove the flame. If you smell rotten eggs at any point, stop. Leave the house, do not use switches, and call 911 or Southwest Gas. This form is not an emergency line.
No glow, after the inducer has run, points at the igniter, the board’s output to the igniter, or a pressure switch that never proved the draft. A cracked igniter can look intact until it is tested. Burners that light for a few seconds and then drop out are the other sequence: the flame is real, and the sensor did not prove it, so the valve closes. Cleaning or replacing that sensor is the usual repair. It is not a reason to assume the heat exchanger is finished.
The wider no-heat sequence, including a blower that never starts, is on furnace not turning on. A light dusty smell on a successful first fire is heater smells burning. Repeated ignition attempts are not a home test. One reset is enough.
Symptoms and how they’re checked
No price column. We do not publish a Sabino Creek igniter or flame-sensor price.
| What you hear | Likely cause | How it’s checked |
|---|---|---|
| Inducer runs, no glow, no flame | Hot-surface igniter, or the board not sending power to it | Watch the sequence. A cracked igniter often looks fine until it is tested. |
| Inducer runs and then stops, with no ignition try | Pressure switch or a vent that is not proving draft | The draft has to prove before the igniter is supposed to glow. |
| Burners light for a few seconds and drop out | Flame sensor not proving flame | The flame is real and the valve closes. The sensor is cleaned or replaced after that is confirmed. |
| Clicking and no flame, over and over | Ignition retries | Stop resetting it. A gas smell means leave and call 911 or Southwest Gas. |
Name, mobile phone, and ZIP are required. Street address can wait. We follow up the same business day by phone or email. That is a callback, not a promise of a repair the same day.