Complies with building regulation part l requirements. For connection to left side of manifold, connecting to flow and return rails. Bypassed flow direction is from flow (red handle) to return (blue handle). Can be used with metal manifold boxes, but not in termobox plastic manifold box.

For connection to right-hand side of manifold, connecting to flow and return rails. Note the flow direction arrows. For this configuration, the flow is on the bottom connection and the return on the top connection. This slimline version can be used with the termobox plastic manifold box. Isolation is not incorporated