Work with 2-, 3- or 4-Wire Zone Valves We’ve enhanced our complete line of Zone Valve Controls with the features and styling you’ve been asking for. Whether you’re looking for switching relays, zone valve controls, priority zoning Circulators, or fan controls, Taco has everything you need. Together with Taco Zone Valve Controls, thermostats, the “00” family of Circulators, and a host of add-on controls, we offer the highest quality and broadest selection of zoning products.