Certain embodiments provide a cover mounted on top of a manifold, the cover comprising an exhaust opening and an inner surface forming a space between the inner surface of the cover and an outer surface of the manifold, wherein the space is configured to receive pressurized gas at an inlet positioned on a first side of a valve. The valve is coupled to the outer surface of the manifold and positioned within the space. The exhaust opening is positioned on a second side of the valve opposite the first side of the valve such that pressurized gas circulates from the inlet around the valve and exits through the exhaust opening.