Why HVAC Zone Damper Actuator Making a Clicking Noise? How to Troubleshoot?

If you ever hear unusual noises coming from your zoned HVAC system, finding the root cause of the problem should become your top priority.

Before tackling the zone damper actuator, make sure that it’s this particular component making the sound. If it is the actuator that’s clicking, then you would have to disassemble the damper and rotate the gear to fresh teeth – a stripped gear is what was producing the noise.

Why HVAC Zone Damper Actuator Making a Clicking Noise? How to Troubleshoot?

In the majority of cases, if your damper actuator is making a clicking noise, it means that there is an issue with the gear – a stripped gear will be producing such a sound.

To fix the problem, you would have to disassemble the damper motor. The gear that you’re looking for is usually large, nylon, and symmetrical, and all you would have to do is rotate the element 180 degrees or to fresh teeth.

If that didn’t help, then you might have to replace the whole assembly as it looks like the stops or the shaft bearings have worn out.

How Do You Troubleshoot Zone Dampers?

  1. Start with a full call for heating and cooling from all the zones. If you don’t feel the airflow from one or more registers, then the damper might be stuck.
  2. Some dampers are easily accessible, others would require you to cut into the ductwork. Evaluate the overall condition of the element, and make sure that it is not covered in dirt or rust.
  3. Verify that the system’s wiring connections are right and that all the wires are in good condition.
  4. Check the damper with a multimeter – when 24 VAC are applied, the element should either open or close. If nothing happens or if the reading isn’t showing 22-27 V, then the damper motor is faulty.

Read: How To Adjust HVAC Automatic Dampers?

Why Is My HVAC Clicking?

If you hear a clicking noise coming from your HVAC system, it might not be the zone damper actuator. Quite a few other elements in the system can be producing such a noise:

  • Clicking is a sign of an obstruction – every time the fan blades hit the object, they will click
  • The noise might be coming from outside the house, in such a case, it is most likely the compressor
  • A damaged capacitor can also click
  • If the heating and cooling system is not turning on but is producing the sound, then an electrical problem might be to blame
  • Finally, a defective thermostat can be constantly clicking

Read: How To Know If HVAC Zone Damper Is Bad?

How Do You Adjust Damper Actuator?

Manual actuators can be adjusted by hand with the help of a metal lever.

If you have automatic actuators, then the chances are high that you’ll be able to adjust them without even getting close to the damper – you can configure the actuator from the controller. The controller can easily adjust the position of multiple dampers at once.

If you hear a clicking noise coming from the actuator, then simply adjusting the damper’s position at the controller will not help. You would have to find a way to access the damper and disassemble it. 

Read: How To Locate HVAC Dampers In Ductwork?

How Do I Know If My Damper Motor Is Bad?

  • You can feel airflow coming from the registers when the damper is supposed to be closed and vice versa
  • The HVAC system is not able to maintain the set temperature
  • The actual motor is showing a reading outside the 22-27 V range when tested with a multimeter

How Do You Test a Zone Damper Motor?

To test the zone damper motor, you are going to need a multimeter. Check for 24V at the damper connections (you would have to be able to access the damper, in such a case) or where it leaves the zone board.

The reading can be a bit higher or lower, but anything outside the 22-27 V range means that the zone damper motor had gone bad. 

Read: How To Troubleshoot A Honeywell Zone Damper?

How Do I Stop My HVAC from Making Noise?

If it’s your damper actuator making the noise, then you would have to either twist the gear or get a new damper.

If any other parts of your HVAC system are producing unusual sounds, you should first figure out what the noise means. It will go away as soon as you fix the root cause of the problem.

Read: Can Zone Damper System Save You Money And Is It Really Worth It?

FAQs

Why Is My AC Unit Making a Ticking Noise?

It is normal for an AC unit to lightly tick as soon as it starts, but repetitive ticking or clicking might indicate a problem with the fan. If the blades are bent, blocked, or broken, the component will be ticking.

Fortunately, in the majority of cases, all you would have to do is replace the blades.

Why Is My Air Compressor Clicking?

If you hear a noise coming from the outside part of your HVAC system, then it’s definitely not your damper actuator. 

The compressor will click if the controls and relays are malfunctioning or damaged. A loose refrigerant tube within the compressor and a loose bolt might also be to blame. 

Is an Actuator and Damper the Same?

An actuator is the ‘interface’ between the control system and the damper. It is a small motor device that uses a low-voltage signal to open and close the dampers.

If you hear a clicking sound coming from the actuator, the chances are high that the damper won’t be able to function correctly.

Why Is My Air Conditioner Clicking On and Off?

An AC will be constantly clicking if there is something wrong with the fan blade.

Low refrigerant levels can also make the system click as the abnormal compressor-pressure levels would cause the compressor to shut off (the AC will restart itself in a bit and the cycle will get repeated). 

How Do I Stop My Vents from Clicking?

Sealing and insulating the ducts would usually help get rid of the majority of noises coming from the vents. 

What Does It Mean When Thermostat Clicks?

A thermostat can click when it starts the cooling or heating cycle and it will click one more time when the cycle ends. It is uncommon for thermostats to make any other noises.

A battery-operated thermostat can start to click if the battery is about to die and that’s pretty much it. 

How Are Damper Actuators Controlled?

Actuators receive a low-voltage signal from the zone control system. The thermostats tell the central control panel when exactly the dampers need to be open, and the control panel passes the signal to the actuators that, in their turn, open or close the dampers.

How Many Actuators Does the Air Conditioning Have?

There are 4 types of actuators in heating and cooling systems. 

  1. Spring return on/off actuators are typically used for the fire and smoke damper.
  2. Air volume modulating actuators are used for the VAV box and the air volume control damper.
  3. Chilled water on/off actuators are utilized for the globe valve and the ball valve of chilled water fan coil HVAC units.
  4. PIBCV modulating actuators are used for the pressure-independent balancing control valves of chilled water AHUs and fan coil units.

How Does a Damper End Switch Work?

The end switch is an element that is typically wired to a fan that starts operating after the damper gets opened.