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12
Table 7 — Configuring Units of Measure in Display
Basic System Functions —
The unit control system
provides over 35 separate unit system and unit control func-
tions. Descriptions of these functions (including purpose of the
function, necessary additional hardware, configuration, and
operating sequence) have been arranged into 11 separate
groups, with each group representing similar topics. These
groups are: Basic Systems, Service, Schedules, Economizer
and Power Exhaust, Smoke Control, Special Ventilation, De-
humidification and Humidifier, Supply Fan Duct Pressure and
VAV Control, Remote Controls, Special Systems, and CCN
Applications.
BASIC SYSTEMS — The basic control systems group of the
unit controls include Standby, Supply Fan Interlock and Opera-
tion, Cooling Stage Control, and Staged Heat Control.
System Type — The unit control system is field-configurable
for Variable Air Volume (VAV) or Constant Volume (CV) air
systems. For VAV systems, the control will maintain the unit
supply-air temperature (SAT) at the user configured set point,
with continuous fan operation during Occupied periods. For
CV systems, the control will maintain space temperature at the
user configured space temperature set point during Occupied
periods.
To check and modify the configuration, the Service function
is used. Press
to log on to the Service function.
Enter the password. Press
to enter into the Factory
Configuration subfunction. Use
to scroll down to
TYPE. The configuration type will be shown (CV or VAV).
Enter new value if appropriate. Press
and
for CV op-
eration. Press
and
for VAV operation. If reconfigured,
enable Data Reset. Log off when completed (unless other
Service functions are to be performed).
If configuring unit for Constant Volume operation, the Fan
Operation Type (Continuous Fan or Auto Fan) must be config-
ured for use in Occupied time schedules. To configure the Fan
Operation Type, enter the Service function. Log on, if required.
Press
to enter the User Configuration subfunction.
Scroll down to Fan Mode (FANM). Select the desired mode
(Continuous = 1, Auto = 0), by pressing
or
and
.
Log off when completed.
Heat Type — Heat type is configured at the factory when fac-
tory-installed gas heating or electric heaters are installed. If
there is no heating element, the control will be configured for
No Heat. If field-installed accessory electric heaters are being
installed or a remote staged heating device will be used, change
Heat Type to 2 (Electric Heat).
If a field-installed hydronic heating device (with modulating
control valve) will be controlled by the unit controls, refer to
the Hydronic Heating section on page 31 for information on
modifying this configuration value.
To check Heat Type, log on to the Service function by press-
ing
. Enter the password. Press
to enter the
Factory Configuration subfunction. Scroll down to the Heat
Type configuration (HEAT). Check value. A value of 0 =
None, 1 = Water/Steam, 2 = Electric Heat, and 3 = Gas Heat.
Press the number
,
,
, or
and
to recon-
figure. If reconfigured, enable Data Reset. Logout when
complete.
STANDBY — Standby is used to disable the unit during in-
stallation or service. A unit in Standby mode indicates the unit
control has been disabled, for purposes of shipping and start-up
or for service activity. A unit which is not in Standby (equiva-
lent to RUN status) indicates unit control has been enabled.
The unit will operate according to occupancy schedules and
function set points. Standby is Mode 25.
NOTE: Units are shipped from the factory in Standby (‘‘STBY
YES’’) mode. Installers must exit Standby to start unit (by
using the HSIO or by using the Remote Start option).
During “STANDBY YES” status, the unit control will stop
all functions. All attempted communication from a CCN net-
work to the unit will be blocked.
During ‘‘STANDBY NO’’ status, the unit control will oper-
ate according to occupancy schedules and appropriate set
points for any and all available functions.
Configuration — To enter into Standby mode, press
to enter the Status function and the Standby sub-
function. Press
to enter standby mode. The display
will read STBY YES.
To exit Standby mode, press
to enter the Status
function and the Standby subfunction. Press
to exit
Standby mode. The display will read STBY NO. See Table 8.
SUPPLY FAN — The Supply Fan Operation Type feature al-
lows user configuration for type of fan operation during Occu-
pied time periods on CV units. The supply fan control function
provides confirmation of operation of the fan to other unit
functions. The fan status pressure switch is checked and then
status is communicated to other modes (where confirmation of
fan operation is required before a function algorithm may ini-
tiate other functions). No additional hardware is required.
Sequence of Operation (VAV) — During Occupied periods,
the control will energize the supply fan contactor. The contac-
tor will close, energizing supply fan motor. The fan wheel will
turn. The airflow switch (differential pressure switch) contacts
close, providing discrete input (DI) to Channel 12 (Closed =
Fan ON). Fan operation will continue through the Occupied
period.
During Unoccupied period with demand, the control will
energize the fan contactor when demand is sensed. After fan
status is confirmed, operating routines will commence. When
demand is removed, routines will end and fan will shut off.
Sequence of Operation (CV, Continuous Fan) — During Oc-
cupied periods, the control will energize the supply fan contac-
tor. The contactor will close, energizing supply fan motor. The
fan wheel will turn. The airflow switch (differential pressure
switch) contacts close, providing discrete input (DI) to Channel
12 (Closed = Fan ON). Fan operation will continue through the
Occupied period.
DESCRIPTION
HOW TO CONFIGURE
SET POINT
RANGE
Select Units of Measure
UNITS
Metric = 1;
English (Imperial) = 0
ENTER
ENTER
ENTER
ENTER
ENTER
IMPORTANT: There are two exceptions to the
Standby status. All Smoke Control functions are active
at all times. If any of the fire/smoke modes become
active, the unit will be controlled with a Force Priority
“FIRE” regardless of RUN/STANDBY/TEST state.
Remote Start input will also override STANDBY OFF
status.
ENTER
CLEAR
ENTER