Gas Fireplace Basics | DIY Gas Fireplace Basics. Gas fireplaces are a great way to add warmth and comfort to a space. Much like wall furnaces, gas fireplaces come on and off with a wall switch and can be controlled by a remote. Fireplaces Installing Heating HVAC Home Improvement Electrical and Wiring Planning.Author: DIY Network Gas Fireplace Schematic - Best Place to Find Wiring and Gas fireplace schematic If you plan to use a ventless fireplace to save money make sure you consider the safety concerns. Some service providers say unvented fireplaces burn more efficiently than their vented gas powered co Some service providers say unvented fireplaces burn more efficiently than their vented gas powered counterparts and cost less which should come with a diagram.