Photo from PVC Vent Screens
For the furnace
The reset button is a red or yellow button situated on the inside of a blower compartment of a furnace. The reset button is the safety feature installed to shut down the furnace.
The reset button on a furnace
The location of the reset button in a motor furnace is different from a Carrier furnace. It is located at the center of the flame roll switch. To reset the Carrier furnace, press the red button that is slightly raised.
Resetting a furnace: Turn the power on and off for a few seconds. This should help resolve any lockout issues and will reset the furnace.
How do you reset a motor reset button?
1. Shut off the main power to the motor at the circuit breaker.
2. Lift up the blower compartment, locate the blower motor and the blower wheel, and search for a red or yellow button.
3. Press the button down and ensure that the furnace has shut down completely.
The reset button can only be pressed once. If it is pressed more than once, this can cause oil to accumulate into the chamber and may result in an explosion.
For the air conditioner
The reset button on the air conditioning system is located in the unit outside of your home. The button will most likely be red in color, with two wires protruding from the top of where the button is. The opposite end of the reset button will have a copper tube connecting to the refrigeration part of the unit.
Photo from NLB Heating and Cooling
Locating the reset button
If you aren’t able to locate the reset button, make sure the main power supply is off and look further into the HVAC unit. Use a stick to spin the fan around, in order to see the deeper parts of the HVAC unit. You can always contact a professional for help if you are having trouble resetting or locating your reset button.