How do I wire a Zone Controller to control a separate supply and return damper actuator?
Type of actuator:
A Zone Controller can control an HVAC unit’s outside and return damper to provide economization, ventilation, and demand ventilation sequences. The type of actuator required on the outside and return dampers is a modulating type; one that accepts a 2-10VDC input. An example actuator would be a Belimo LMB24-SR.
Wiring a Zone Controller to the supply and return damper actuators:
When wiring an outside and return damper for economizer, ventilation, and demand ventilation sequences: you will need to use the correct Analog output from the Zone Controller to control these actuators. Please reference the Zone Controller’s installation guide or the following tablet below*:
Control Point | Option 1 | Option 2 | Option 3 |
---|---|---|---|
Variable Speed Fan | (A1) | Not Used | Not Used |
Outside/Return Damper | (A2) | (A1) | (A2) |
Bypass Damper | Not Used | (A2) | Not Used |
* How to read the above tablet:
- Control Point is a point at the HVAC unit that the Zone Controller will control.
- Options are the different combinations that can be wired to the Zone Controller.
- (A1) or (A2) means that if that combined option is used, then that control point needs to be wired to the shown analog terminal number.
- Not Used means that that combined option does not use that control point.
- (A3) and (A4) these terminals are not shown in the above table because they are used for modulating heating and cooling only.
Wiring Process to the Outside and Return Damper Actuators:
- Using standard 18G unshielded thermostat wire, wire the correct analog output from the Zone Controller (from the above tablet) to the 2-10VDC input of both the outside and return damper actuators.
- Use a second 18G unshielded thermostat wire and wire the common (C) terminal from the Zone Controller to the common (-) terminal from both the outside and return damper actuators. You will also need to connect the common (-) terminal from both the outside and return damper actuators to the actuator’s power source.
- Use a third 18G unshielded thermostat wire and wire power, normally either 24VAC or 120VAC, to both the outside and return actuators (+) terminal. Follow the actuator manufacturer’s recommended instructions for providing the correct power source to both the outside and return actuators. Make sure not to wire any form of external power to the (A1), (A2), (A3), and (A4) terminals on the Zone Controller. This can damage the Zone Controller’s internal hardware.
- If your outside actuator provides a feedback signal, use a fourth 18G unshielded thermostat wire to connect the correct feedback terminal from the Zone Controller to the 2-10VDC feedback output at the outside damper actuator. Do not wire the feedback to the return damper actuator, this is not needed.
Test the dampers:
You will need to set the return and outside actuators to move opposite of each other. For example, if the Zone Controller outputs 10VDC the outside dampers will be at 100% open and the return damper would be at 100% closed.
You will want to finish configuring the Zone Controller through the Pelican App in order to test the dampers move correctly.
Once configured, you can turn the Cooling or Heating to On at any of the zone thermostats that communicate to this Zone Controller and the Zone Controller will open the outside damper to the configured Minimum Damper Position configuration. If you temporarily set the Minimum Damper Configuration to 100%, then the outside damper should go to 100% open and the return damper should go to 100% closed.
During testing if one of the actuators is not moving in the correct direction, the actuator will normally have a toggle on it that allows you to change the direction it is moving.
What about a modulating exhaust damper actuator?
Yes, you can also wire a modulating exhaust damper’s actuator to the Zone Controller. Follow steps 1 through 3 above, but do the same for the exhaust damper actuator. The exhaust damper will need to move in the same direction as the outside damper. For example, if the outside damper is 100% open, the exhaust damper should be 100% open.