A Bad Actuator Could Keep Your Zoned AC From Cooling Your House Properly

If your home has zoned air conditioning, you might also have automatic dampers. Dampers are discs inside ducts that close off airflow completely or partially. Some dampers are operated by hand, but automatic dampers are common and more convenient.

These dampers are controlled by actuators that change the position of the dampers. If an actuator goes bad, your zoned system won't work properly. Here are signs of a bad actuator and how an air conditioning repair service can help.

How to Tell a Damper Actuator Is Bad

When an actuator that controls a damper is bad or malfunctioning, the damper itself may be erratic. It may open fully and stay that way, or it may close off airflow completely and not open again. This results in a zone of your home becoming too cold or too hot. Plus, you'll notice the thermostat isn't able to control the temperature in the zone if the damper stays in a partially opened position.

How Contractors Diagnose Bad Dampers

The damper relies on a low voltage signal from the control board to operate. If something is wrong with the thermostat, control board, or wiring, the damper may not act as it should. There could also be a problem with the damper disc. It might be stuck and unable to respond to the signal from the actuator.

An air conditioning repair technician has to rule out all these causes of a damper malfunction and test the actuator to determine the exact cause of the problem. The technician performs a visual inspection and runs tests to pinpoint the issue.

How Contractors Replace Bad HVAC Actuators

If the actuator is found to be bad, it will probably have to be replaced. If another cause is to blame, and the problem is fixed, such as releasing a stuck disc or tightening wiring, then the actuator may start working again.

An actuator is usually located on top of a duct, so it should be easy to access. The technician chooses the right part for your brand of equipment and then swaps the actuator out. This involves disconnecting the wires from the control board, unscrewing the actuator from the duct, and disconnecting the actuator from the damper. Proper installation of the new actuator is important, since the damper won't work if the wiring isn't attached properly.

Once the new actuator is in place, the air conditioning repair technician tests it by changing settings on the thermostat and checking for airflow. The zoned system settings are then set and your home should cool down the way you want it to again.