Energy Efficient Water HeaterFacebook Twitter Pinterest Email Print Video Playback Not Supported The Vertex gas hot water heater from A.O. Smith has an impressive 96% thermal efficiency rating. The unit can reduce your water heating costs by up to 50%, and is so efficient that a PVC pipe can be used to vent the water heater to the outside.Watch this video to find out more.Further InformationChoosing a Hot Water Heater (article)Energy Efficient Hot Water Heaters for Your Home (video)Solar Hot Water Heaters for Your Home (video)How to Save Energy on Hot Water Heaters (video)