A service unit including a vessel defining a chamber configured to receive fluid. A first conduit is coupled to the vessel and is in fluid communication with the chamber. The first conduit defines an inlet. A second conduit is coupled to the vessel and is in fluid communication with the chamber. The second conduit defines an outlet. The first conduit, the chamber, and the second conduit define a fluid passageway, and the fluid is unpressurized when in the chamber.