My friend recently had an 80% draft induced forced air gas furnace installed. The furnace shares a b-vent with a natural draft gas water heater. The water heaters vent connector is installed correctly above the furnaces vent connector. I read on the nachi site that natural draft appliances should not share a vent because of the pressure that draft induced furnace creates. The furnace and water heater are in enclosed room ,but they do have sufficient air supply. Should he worry about this or are their new guidelines permitting this installation
Safe At Home Inspections,Inc.