Boiler & Heating Zone Valves
Zone valves enable different areas, floors or rooms, to be independently temperature controlled. In conjunction with thermostats, zone valves make heated spaces far more comfortable for the building’s occupants and lower fuel bills by directing the energy to where it’s needed. Typically, zone valves consist of two parts; the valve body and the actuator head. In the majority of cases, these parts can be replaced separately. The head contains a motor to rotate the valve shaft between the open and closed positions. Note that the valves are spring-loaded to be in “normally open” or “normally closed” positions until the power is applied. When power is discontinued they return to their default position (with closed being the most common type). Many also have a manually operated lever, useful for filling, draining and testing operations. Where there are multiple zone valves in use, zone valve controllers can be inserted between them and the boiler and pump to simplify both operation and wiring. Zone valves also differ in their wiring, some having 2, 3 or 4 terminals. In the latter, 2 will go to an end switch that delays the start-up of the pump until the valve is fully open. This prevents potentially damaging surges. If there is pipe noise on start-up, check that the zone valve has been correctly oriented on the pipe. Top brands Reliability requires precision engineering, so all of our zone valves are sourced from manufacturers with decades of experience. These include Sauter of Switzerland, American giant Honeywell, and of course Scottish company Sunvic.