AAON Orion VCCX2 User Manual

10
VCCX2 Controller Technical Guide
Variable Air Volume Unit
The VCCX2 can control VAV units that are typically designed
for occupied Cooling Mode only, where VAV boxes equipped
with reheat satisfy heating demands in individual spaces. In this
application, unit heat is typically used for Morning Warm-Up.
Morning Cool-Down is also available. The controller can be
congured to control the supply fan VFD to maintain a duct
static pressure setpoint.
The VCCX2 can also control VAV units that may require
occupied Heating operation to “temper” the outdoor air if it is
too cold outside for the mixed air to maintain the Cooling Supply
Air Setpoint.
Constant Air Volume Unit
The VCCX2 can be congured for Constant Volume applications,
that are typically Space Temperature or Return Air Temperature
controlled.
The VCCX2 can also be used for restaurant kitchen or lab
applications that are 100% Outdoor Air part of the time and
recirculating air part of the time. A Hood On binary contact
closure input forces the VCCX2 to switch to 100% Outdoor Air
control based on an exhaust hood switch activation. The VCCX2
requires Outdoor and Indoor Air Temperature (and Humidity)
Sensors to accomplish this application.
Single Zone VAV
This is a hybrid CAV/VAV application for a unit serving a single
space and using Space Temperature Setpoints to enable Heating
and Cooling Modes. Heating and Cooling are controlled to their
respective Supply Air Setpoints while the supply fan modulates
to maintain the Space Temperature Setpoints. Single Zone VAV
applications can be congured for VAV Cooling and either VAV
or CAV Heating. Single Zone VAV operation requires the use of
modulating Heating or Cooling sources.
Space Temperature Control of High
Percentage Outdoor Air Units
This application allows the unit to be congured to use the
space temperature to initiate Cooling and Heating Modes on
units that are high percentage outdoor air or 100% outdoor air
units. Before entering the space Vent Mode, the controller will
rst determine if the outdoor air temperature is above or below
special outdoor air Cooling and Heating setpoints. If so, the unit
will leave stages of Cooling or Heating on as necessary to achieve
a neutral supply air temperature – thus avoiding dumping very
hot or cold air into the space.
Make-Up Air Unit
The VCCX2 can be congured for 100% Outdoor Air control
for Make-Up Air units. All HVAC Modes are determined from
the Outdoor Temperature and Humidity Sensors. The Outdoor
Air Volume should be at least 50% or higher to be congured
for Outdoor Air control.
AAON
®
Return Air Bypass Control
This control scheme can only be used on Constant Volume
HVAC units that are equipped with a Return Air Bypass Damper
and that use Space Temperature and Humidity Sensors as the
Controlling Sensors.
AAON
®
Return Air Bypass Control provides improved moisture
removal capabilities while utilizing internal space loads for
reheat by redirecting Return Air from the upstream side of the
DX Evaporator Coil to the downstream side of the coil during
Dehumidication.
Zone Voting
The VCCX2 can be congured to be the unit controller in a
zone voting system where the individual zones vote to put the
unit into occupied Cooling or Heating Mode. To be used in this
application, Orion zone controllers must also be used in order
to allow communication between the zones and the VCCX2
Controller. Duct static pressure control can be accomplished
with a supply fan VFD or a bypass damper.
OVERVIEW
Applications

AAON Orion VCCX2 Specifications

General

Brand	AAON
Model	Orion VCCX2
Category	Controller
Language	English