Most standard 24VAC duct dampers use three control wires: Drive Open, Common and Drive Closed. This is the quick wiring reference for that arrangement.
Quick wiring map
| Terminal group | Damper connection | Function |
|---|---|---|
| 1 & 2 | Drive Open | Commands the damper open |
| 3 & 4 | Common / neutral | 24VAC return (commonly labelled Common on the actuator) |
| 5 & 6 | Drive Closed | Commands the damper closed |
Match the three damper leads to their labelled function: Open → 1/2, Common → 3/4, Close → 5/6. The terminal numbers identify the open, common and closed groups; follow the labels on the controller and actuator before connecting anything.
Before you connect it
- Turn off the 24VAC control supply before moving wiring.
- This guide is for a 24VAC, three-wire, drive-open/common/drive-closed actuator. It is not a wiring diagram for a two-wire spring-return damper.
- RJ11/RJ12 plugs and wire colours are not a universal standard. Identify each conductor by its function, not by plug position or colour alone.
- Never bridge the open and close connections. Test one zone at a time after power is restored.
Which TekOnline controller should I choose?
For a standard three-wire damper and individual timed positioning, choose the TekOnline 8-Zone HVAC Controller V3. For a wall-mounted four-zone project, see the 4-Zone Wall Controller. The 8-Zone V2 remains a practical general 24VAC zone-control option.
Still checking compatibility?
Start with the HVAC zone-controller compatibility matrix, then compare the actuator label and wiring. If you are reusing ZoneMaster ZoneSwitch V2 dampers, read the ZoneMaster damper guide. If anything does not clearly say 24VAC Open / Common / Close, send a photo of the controller, actuator label and wiring before ordering.
FAQ
Is “neutral” the same as common here?
For this low-voltage AC control circuit, the return conductor is commonly marked Common. Some field notes call it neutral; use the actuator’s own label as the source of truth.
Will this work with any three-wire damper?
It applies to a conventional 24VAC actuator labelled Open, Common and Close. Confirm the voltage and function labels first: physical plug styles and pinouts vary between brands.
What if the damper has only two wires?
Stop and check the actuator type. A two-wire spring-return damper uses a different control arrangement, so use the compatibility matrix or request a compatibility check rather than applying this three-wire map.