Hello, I currently have a aging elec water heater in the cellar of my home. I have Natural Gas to the house and would love to change to a Nat Gas water heater. So here is my question. Can I vent the water Heater out through the side wall, or would I need to get a blower unit with my water heater?I would like to avoid the extra cost of the blower. I have gotten differing answers about this and know that propane for sure needs to be power vented or a verticl chimney, But how about Natural Gas. Thanks