Distech Controls VA-024ZS Series Manual

Hardware Installation Guide
VA-024ZS Series
Zone Valve Actuator, 24lb., Spring Return
Figure 1: VA-024ZS Series zone valve actuator
Product Description
This document describes the hardware installation procedures for the
following VA-024ZS Series zone valve actuators:
VA-024ZSC120D
24lb., Spring Return, Normally-Closed, 120V,
Digital
VA-024ZSC024D
24lb., Spring Return, Normally-Closed, 24V,
Digital
VA-024ZSO120D
24lb., Spring Return, Normally-Open, 120V,
Digital
VA-024ZSO024D
24lb., Spring Return, Normally-Open, 24V,
Digital
General Installation Requirements
For proper installation and subsequent operation of each actuator, pay
special attention to the following recommendations:
- Upon unpacking the product, inspect the contents of the carton for
shipping damages. Do not install damaged actuators.
- Avoid areas where corroding, deteriorating or explosive vapors,
fumes or gases may be present.
- Ensure that all equipment is installed according to local, regional,
and national regulations.
Personal injury or loss of life may occur if you do not follow a
procedure as specified.
Equipment damage or loss of data may occur if you do not
follow a procedure as specified.
Take reasonable precautions to prevent electrostatic
discharges to the controller when installing, servicing or
operating the controller. Discharge accumulated static
electricity by touching one’s hand to a well-grounded object
before working with the controller.
Mounting Instructions
Required Tools
- Small flat-blade screwdriver
- Wire stripper
Estimated Installation Time
- 20 minutes
1. If mounting the actuator to a valve already in line:
- Close the shut-off valves in the piping (upstream first,
then downstream).
OR
- Switch off the pump to allow the differential pressure in
the valve to drop.
2. Disconnect the controller power before replacing the
actuator.

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The vertical position is recommended for mounting.
Figure 2. Acceptable Mounting Positions.
Actuators must not be exposed to condensed/dripping
water. If the actuators are installed below piping that can
drip condensate, either the actuator needs to be protected
by shielding to deflect the water drip or the piping needs to
be insulated to prevent condensation.
Actuator housing must not be in contact, or close proximity
to adjacent hot water supply or return piping.
Loosen retaining ring and rotate actuator if necessary, to
avoid proximity or contact with hot water supply or return
piping, then re-tighten ring to maintain desired orientation.
Installation
The black actuator attachment support ring must be in place
on top of the valve bonnet before installing the actuator.
If the support ring is not in place, damage to the actuator
connection may result.
Mounting the VA-024ZSO Series Actuator to a Valve
1. Place the actuator on the valve and firmly hand-tighten the coupling
piece.
2. Connect the wires. See Wiring.
Mounting the VA-024ZSC Series Actuator on a Valve
1. Rotate the manual override lever and latch.
2. Place the actuator on the valve and firmly hand-tighten the
coupling piece.
Failure to fully rotate the manual override handle beforehand
tightening will hinder proper valve close off.
3. Release manual override handle.
4. Connect the wires. See Wiring.
Figure 3. Mounting the Actuator on a Valve.
The installation is now complete.
Removing the Actuator from a Valve
1. Disconnect the wiring.
2. Unscrew actuator-coupling piece from the valve body threads.
3. Remove the actuator from the valve.
Wiring
- All wiring must conform to NEC and local codes and regulations.
- Use earth ground isolating step-down Class 2 transformers.
Do not use autotransformers.
- Determine the supply transformer rating by summing the total VA
of all actuators used. The maximum rating for a Class 2 step-
down transformer is 100 VA.
It is recommended that one transformer power no more
than 10 actuators
- VA-024ZSC024D / VA-024ZSO024D, 24 Vac actuators: Wiring
connection can be made inside the actuator housing (remove the
housing top for access).
- VA-024ZSC120D/VA-024ZSO120D, line voltage actuators: Wiring
connection requires junction box and flex conduit no further than
15 inches (381 mm) from actuator.
G0 and G must be properly wired for correct function and full
life of the actuator.
Figure 4. 24 Vac Actuator Wiring Diagram.
Figure 5. 120 Vac Actuator Wiring Diagram.
Manual Override
For manual positioning, rotate the manual override handle clockwise
180°, and squeeze it to latch around protruding stop. See Figure 6.
The actuator will automatically unlatch when power is
applied.

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NOTE:
The "0" and "1"
position markings
are intended for
reference only and
not stroke
measurement.
Override handle
at position 0.
Override handle at
position 1.
Figure 6. Manual Override Handle Position.
Start-Up
When the manual override handle is at the "0" position, the output shaft
is retracted if the actuator is normally open, or extended if normally
closed. See Figure 7.
When the Manual Override handle is rotated to position 1, the reverse
is true. See Figure 8.
Check the wiring and the position indication.
(A) Allow handle to turn counterclockwise to retract spindle.
(B) Turn handle clockwise to extend spindle.
Figure 7. Normally Open (VA-024ZSO Series).
(A) Allow handle to turn counterclockwise to extend spindle.
(B) Turn handle clockwise to retract spindle.
To avoid damage to actuator, DO NOT manually assist
spring return.
Figure 8. Normally Closed (VA-024ZSC Series).
Service Envelope
Minimum access space recommended: 8 inches (200 mm) above the
actuator.
Troubleshooting
Check the wiring for the proper connections.

©, Distech Controls Inc., 2014. All rights reserved.
While all efforts have been made to verify the accuracy of information in this manual, Distech Controls is not responsible for damages or claims arising from the use of this
manual. Persons using this manual are assumed to be trained HVAC specialist / installers and are responsible for using the correct wiring procedures and maintaining safe
working conditions with fail-safe environments. Distech Controls reserves the right to change, delete or add to the information in this manual at any time without notice.
Distech Controls, the Distech Controls logo, and Innovative Solutions for Greener Buildings are trademarks of Distech Controls Inc. All other trademarks are property of their
respective owners.
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VA-024ZS Series_IG_10_EN
Dimensions
Figure 9. Dimensions of the Actuator Shown in Inches (Millimeters).