Furnace Won't Start Automatically. The home’s thermostat is off or set incorrectly. Here’s a short list of the most common reasons why your heating oil furnace won’t start up.

Why Won't My Furnace Stay On? from blueaironenj.com

The home’s thermostat is off or set incorrectly. There’s no electricity reaching the home. The emergency burner shut off switch was engaged.

The Emergency Burner Shut Off Switch Was Engaged.

Here’s a short list of the most common reasons why your heating oil furnace won’t start up. There’s no heating oil in the tank Remove the front panel and look for the igniter/sensor.

It Is Usually Located Near Where The Flames Shoot Out Of The Burners.

There’s no electricity reaching the home. The home’s thermostat is off or set incorrectly. Refer to your user manual to locate the igniter.