It shows the parts of the circuit as streamlined shapes and also the power and signal links in between the devices.
Gas fireplace switch wiring.
A wiring diagram is a simplified traditional pictorial representation of an electric circuit.
Assortment of gas fireplace wiring diagram.
If the fireplace is a 120v control then in most cases you will need a neutral.
Crimp the connectors securely to the wires.
The thermopile in your fireplace puts out millivolts nothing near the 120v the light switch was designed for.
Slide the spade connectors onto the spade terminals on the back of the switch in the control panel or connect them directly to the pigtail wires if installed.
A generic low voltage switch from a electronics store or ripped out of a toy would probably do it for example a 12v spst.
Slide the provided spade connectors onto the stripped ends of the wires in the gas fireplace control panel.
When attempting to automate a fireplace with a smart switch you have a problem because a lot of switches require a neutral wire to be connected so they have constant power for the zwave radios to send and receive signals.
If this is the case there will be no power to run the smart switch unless it is battery powered.