Overview

In order to control my gas fireplace I needed a way to connect two DC wires that tell the fireplace to turn on. Previous to this modification, these two wires were connected to a regular wall switch. This modification allows for me to control the fireplace via the Sonoff as well as a wall switch.

Modifications to the Board

We need to disconnect the Line input into the Relay. To do this, we can cut the board as depicted in the pictures below. Afterwards, verify that there is no connection between Line In and the relay input.

The second modification was to join the relay inputs. Doing this would join cause the output to connect/close when the relay is activated which is exactly what we want to turn on the fireplace.

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Complete Setup

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