The VA2500. 2500N thrust and VFA2000. 2000N thrust (spring return) valve-actuators are used to control valves in HVAC systems. This new actuator is self-adjusting and therefore has a greatly reduced installation and commissioning time. They are of modular construction so that for instance, the required type of control signal is achieved simply by fitting a module with the required function in-situ. Valves intended for use with the VA2500 are the Johnson Controls VG9000 PN6 & PN10 flanged valves and the VG8000 / VG8300 series PN16 & PN25 flanged valves. All actuators are self adjusting, have a manual operation capability and a maximum stroke of 49mm.