Useful in colder climates for preventing freezing air from flowing back into the heat exchanger and freezing it and damaging the heaterSpecifications:• Vent material: AL29-4C stainless steel Compatibility and cross reference:This item is the same as Takagi, AO Smith, American Heating part number 9007996005. It is compatible with the following tankless water heaters, as shown in their manual: American Water Heaters GT-510-P/N Indoor Liquid Propane/Natural Gas FAQ (Frequently Asked Question)Q1: Is this 4" adapter with backflow preventer available in 5" diameter, too? A1: Yes, here is the 5" version of this appliance adapter with backflow preventer. Here is an appliance adapter, backflow preventer, that also includes a condensate collector and drain if you need it for 3", 4", or 5" diameter pipe. If you do not need the drain hole, Z-Flex tech support instructs to simply plug it. And, you can also buy the Universal Appliance Adapter with no backflow preventor, and buy the backflow preventer alone here. DownloadsZ-Vent SVE Series IV Installation and Maintenance Instructions, 3" to 24", Single & Double Wall |