Abstract: A flow control valve for selectively routing a coolant in a dual-zone heater system is provided. The flow control valve includes a housing and a flow control device. The housing includes an inlet port, a bypass outlet, a front heater outlet, and a rear heater outlet communicating through an internal cavity. The flow control device, which can be a cylinder, sphere, etc., is rotatably positioned in the internal cavity. The flow control device has an axial channel and generally radial aperture. The axial channel transports the coolant received from the inlet port through the flow control device, and the aperture delivers the coolant to one or more of the bypass outlet, the front heater outlet, and the rear heater outlet as the flow control device is rotated. In this way the circuit is not deadheaded.

Abstract: A seal for sealing a flow control valve is provided. The seal includes an inlet configured to mate with a flow control device, an outlet configured to mate with a housing, and a convolution formed in a seal wall and interposed between the inlet and outlet. The convolution expands the seal wall when a differential pressure across the convolution is increased.