My house already had a forced air gas furnace in place when we moved in. There is air duct installed inside walls plus ceilings that carries heated air to each of the rooms. The stale air is drawn out plus heat is introduced through supply plus return vents. I’m not overly impressed with the operation plus comfort level provided by this category of gas furnace. Since heat naturally rises, the highest temperatures are near the ceiling. As soon as the heat leaves the vents, it floats straight upward. Unless I want to sit on a ladder, it does myself and others little good. I need to set higher thermostat settings in an attempt to keep the lower half of the room acceptablely warm. Plus, the air from the ducts often carries contaminants such as dust, bacteria, pollen, dander plus mold spores. It drawbackly impacts the health plus cleanliness of the home. During the Winter months, I need to dust plus vacuum a lot more often. There’s also concerns with overly dry air plus energy losses because of the leaks plus holes in the air duct. The average duct plan allows approximately 30% of conditioned air to escape. A perfectly diagnosed duct plan still sacrifices around 4% of the heated air. The gas furnace is also noisy. I wish it was feasible to tear out the gas furnace plus replace it with a boiler gas furnace. A boiler uses water rather than air to convey heat. The operation is virtually silent plus as a closed system, it’s especially clean. The heat is radiating into the air rather than blown in, so the highest temperature remains near the floor. There’s no drafts, no chilly spots or temperature stratification plus because water heats up quicker than air, the boiler doesn’t need to toil as hard.