How To Turn On Furnace Without Thermostat. Go to the thermostat and turn it to off and the fan to auto. Next, air passes through the air filter before it’s heated and recirculated back into your home.
Turn the power on to the hvac at the circuit breaker. Exposure to direct sunlight, heat emissions, and outside temperatures will give your thermostat an inaccurate reading, thereby triggering your furnace to turn on and off when it shouldn’t. Turn off the power on the air conditioning and furnace units associated with your thermostat.
Due to advanced manufacturing, your furnace simply will not run without these backups in place.
This simple step is often overlooked. Furnaces without a pilot light have a simpler series of steps: The blower can also be used without the furnace burner’s ignited. If it works you will have to turn off breaker to shut it down.