What does "Actuator Stuck on Open Position" mean?

What does "Actuator Stuck on Open Position" mean for an in-suite fan coil system?

An actuator is a device that controls the opening and closing of a valve or cartridge in a condo fan coil system. In a fan coil system, the actuator controls the flow of hot or cold water through the coil, which determines the temperature of the air blown into the room.

If the actuator is stuck in the open position, it means that the valve or cartridge it controls is stuck in the fully open position. This can result in the fan coil system blowing air that is either too hot or too cold, depending on the season.

When an actuator is stuck in the open position, it typically indicates a problem with the actuator itself or the valve or cartridge it controls. It's possible that the actuator has malfunctioned or failed, or that there is an issue with the valve or cartridge and they may also need to be replaced.

To fix this issue, an HVAC technician will need to inspect the actuator and the valve or cartridge it controls to determine the cause of the problem. Depending on the issue, the technician may need to replace the actuator, cartridge, valve or possibly all three parts may need to be replaced.