Z-Flex Universal Appliance Adapter, Condensate Drain, Backflow Stop 3" 4" 5"
Useful in colder climates for preventing freezing air from flowing back into the heat exchanger and freezing it
Also, use this part to drain condensate from high-heat appliances, especially "non-condensing" tankless water heaters. Condensate drain tube is sold separately here.
• 3", 4" or 5" diameter sizes available
Compatibility and cross reference:
The 4" diameter version of this item 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