Yes, a gas fireplace is an excellent heating-source, and it’s also an attractive unit. Some models can very quickly heat around 1000 to 1500 square feet. You can use a gas fireplace quite safely as a primary source of heating small apartments or homes. But, for larger spaces, you should not rely on a single fireplace to evenly distribute heat to every corner of your home.
For your living room, you can use a gas fireplace as the primary source of heat. For places that are far away from the living space, this will work only as a secondary heating source.