The Rain Harvesting 90mm Air Gap creates an open break in a tank overflow pipe to help prevent backed-up stormwater reaching the stored rainwater. Screens at the opening help keep mosquitoes out while excess tank water drains into the pipe below.
The fitting installs in a vertical section of pipe after the tank overflow. Its upper outlet discharges across the open gap into the lower section, separating the tank from the stormwater pipework below.
Install with the marked side facing up and allow access to the screens. The 90mm model requires a 142mm section of pipe to be removed, with both sockets solvent welded to matching pipe. The installation height must suit the drainage arrangement, including whether the stormwater line remains charged with water.
Inspect the screens regularly and remove any dirt or debris. Refit them securely after cleaning to maintain the insect barrier.
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