What component is used when two storage tanks serving the same area have different overflow elevations?

The altitude valve is specifically designed to manage the flow of water between two tanks that serve the same area but have different overflow elevations. Its primary function is to regulate the filling of the tanks based on their water levels, ensuring that the tank with the lower overflow elevation fills up to its designated level without overflowing while allowing the tank with the higher elevation to function optimally.

When the water level in the lower tank reaches a predetermined point, the altitude valve opens, allowing water to flow from the higher tank into the lower tank until the water level in the lower tank is sufficiently low. This prevents overflow from the lower tank, maintaining proper water levels and ensuring efficient water supply management.

The other components listed serve different functions. A pressure regulator maintains a set pressure in a system, a flow control valve regulates the flow rate regardless of pressure, and a check valve prevents backflow, none of which are specifically aimed at managing the overflow concerns that arise from tanks with differing elevations.