Messana – Thermal Actuators

Two-wire 24V slow opening thermal actuator (without end switch) for radiant cooling and heating manifolds. It is compatible with most common manifolds using a standard threaded ring adapter. It comes with a VA10 ring adapter that also works with the Messana manifold (other adapters are available). The actuator mounts on the manifold loop by snapping onto the pre-installed ring adapter. It is normally closed (NC), when energized, it opens the loop valve to allow the activation of the related zone. The actuator mechanism is based on a PTC resistor-heated elastic element and a return compression spring. When the elastic element is heated by applying the nominal 24V voltage to the PTC resistor, it expands and moves an integrated plunger to open the valve. When the PTC resistor stop being energized, the elastic element shrinks and the return compression spring moves the plunge back and closes the valve.