AAON VCCX-IP User Manual

30VCCX-IP Controller Technical Guide
SEQUENCE OF OPERATIONS
Conguration Options
Supply Fan Operation
Any time the supply fan is requested to start, a one-minute minimum
o timer must be satised. If the timer is satised, the supply fan
relay is activated while all other outputs are held o until their
minimum o timers have been met.
Upon going into the Occupied Mode or upon power-up, the
controller will initiate a user-adjustable fan starting delay to provide
a staggered start for systems with several HVAC units.
To protect the dampers on MUA systems on startup, dampers open
then the fan starts after the fan starting delay setpoint time expires.
On shut down, the fan turns o rst. The dampers close after the
fan starting delay setpoint time expires or fan proving is deactivated.
In Fan Cycle Mode or when going Unoccupied, the supply fan is
held on for 10 seconds after Cooling has staged o or after Leaving
Vent Mode and 90 seconds after the Heating has staged o.
Purge Mode
When going into Occupied Mode, an optional Purge Mode is
initiated. The fan runs with the economizer closed, and all cooling
and heating is de-energized. The length of the Purge Mode is user
adjustable.
Occupied Mode
The supply fan can be congured to run continuously (default) or
to cycle with Heating, Cooling, or Dehumidication.
Unoccupied Mode
Upon going Unoccupied, the Cooling or Heating will turn o
immediately. The fan will then turn o in 30 to 60 seconds. Typically,
thereafter, the supply fan will cycle on a call for Heating, Cooling,
or Dehumidication. The supply fan can also be congured for
continuous operation during Unoccupied Mode.
HVAC Source Conguration Options
The VCCX-IP Controller can be congured to have various HVAC
source options that will determine the mode of operation (Heating,
Cooling, or Vent Mode) of the unit. The following are descriptions
of those options.
Space Temperature
Typical selection for CAV recirculating units.
Return Air Temperature
Optional selection for CAV recirculating units.
Single Zone VAV
Selected for a space temperature controlled single zone VAV
application.
Single Zone VAV with High Outdoor Air %
Provides SZVAV operation on units with high percentage of outdoor
air. By tempering the supply air during the Vent Mode of operation,
the unit will try to prevent dumping of hot or cold air into the space.
Outdoor Air Temperature
Typical selection for 100% outdoor air (MUA) or high percentage
outdoor air units.
Supply Air Temperature
Selected for Cooling Only. VAV units with optional morning Warm-
Up/Cool-Down.
Supply Air Tempering
Selected for VAV units maintaining a Cooling Setpoint with cooling
or heating as required that may need heat to temper the supply air
temperature during very cold conditions.
Space Temperature with High Outdoor Air %
Provides space temperature (instead of outdoor air temperature)
control of 100% or high percentage outdoor air units by tempering
the air during the space Vent Mode of operation to prevent dumping
of hot or cold air into the space.
DOAS Unit (Supply Air Dew Point Control)
Selected for DX-DOAS units using 100% outdoor air and have an
EBUS supply air temperature and humidity sensor installed.
HVAC Mode Set by Remote Contact
Provides for wet contact closures to force the unit into Heating,
Cooling, and Dehumidication Modes. If this option is selected, it
applies to all three modes, and all three modes will only be initiated
by these contact closures. If both the heating and cooling contacts
are made, the unit will be in Vent Mode.
Occupied/Unoccupied Mode of Operation
The VCCX-IP Controller can utilize several methods for determining
the Occupied Mode of Operation. These are as follows:
• Forced schedule
• Remote forced occupied signal
• Internal week schedule
• Push-button override signal
• Broadcast week schedule from GPC-XP
The VCCX-IP Controller can be forced into the Occupied Mode by
inputting a forced schedule from any operator interface.

AAON VCCX-IP Specifications

General

Brand	AAON
Model	VCCX-IP
Category	Controller
Language	English