Multi-Stage Constant Volume Units With; Mechanical Thermostat; Space Sensor; Economizer Options - Carrier 48AJ Operating And Service Manual

Multi-Stage Constant Volume Units with

Mechanical Thermostat —
form the following:
1. The unit is shipped with the unit control disabled. Enable
the control by setting Local Machine Disable (Service
→
Test STOP) to No.
→
2. Under Configuration
(TSTAT MULTI).
3. Remove jumpers from R-W2 and W2-W1 on TB4 in the
control box. Connect thermostat to TB4.
4. Under the Setpoints
configurations:
SA.HI Supply Air Set Point Hi
SA.LO Supply Air Set Point Lo
5. See the Economizer Options section on this page for ad-
ditional economizer option configurations.
6. See the Exhaust Options section on this page for addition-
al exhaust option configurations.
Multi-Stage Constant Volume Units with
To configure the unit, perform the
Space Sensor —
following:
1. The unit is shipped with the unit control disabled. Enable
the control by setting Local Machine Disable (Service
→
Test STOP) to No.
→
2. Under Configuration
(SPT MULTI).
3. Install jumpers between R-W2 and W2-W1 on TB4 in
the control box.
4. Under the Setpoints menu, the following configurations
should be set:
OHSP Occupied Heat Setpoint
OCSP Occupied Cool Setpoint
UHSP Unoccupied Heat Setpoint
UCSP Unoccupied Cool Setpoint
GAP Heat-Cool Setpoint Gap
SA.HI Supply Air Set Point Hi
SA.LO Supply Air Set Point Lo
5. The degrees of demand from the space temperature set
points are configured under the Configuration
submenu. See the Heating Control and Cooling Control
sections for further description on these configurations.
Configure the following set points:
L.H.ON Demand Level Lo Heat On
H.H.ON Demand Level Hi Heat On
L.H.OF Demand Level Lo Heat On
L.C.ON Demand Level Lo Cool On
H.C.ON Demand Level Hi Cool On
L.C.OF Demand Level Lo Cool On
→
6. Under Configuration
the space sensor by setting SPT.S to ENBL.
→
7. Under Configuration
for continuous fan or 0 for automatic fan.
8. To program time schedules, set SCH.N=1 under Config-
→ →
uration CCN SC.OV
trol to use local schedules.
→
9. Under the Timeclock
sired schedule. See Time Clock section for further
descriptions of these configurations.
To configure the unit, per-
→
UNIT C.TYP, set C.TYP to 3
menu, set the following
→
UNIT C.TYP, set C.TYP to 5
→
D.LV.T
→ →
UNIT SENS SPT.S, enable
→
UNIT CV.FN, set CV.FN to 1
→
SCH.N to configure the con-
SCH.L submenu, enter the de-
10. See the Economizer Options section below for addition
economizer option configurations.
11. See the Exhaust Options section below for addition
exhaust option configurations.
Economizer Options —
ECON submenu, the following set points should be configured:
EC.EN Economizer Enabled?
EC.MN Economizer Min.Position
EC.MX Economizer Maximum Position
E.TRM Economizer Trim for SumZ?
E.SEL Econ Changeover Select
OA.E.C OA Enthalpy Change Over Select
OA.EN Outdoor Enthalpy Compare Value
OAT.L High OAT Lockout Temp
O.DEW OA Dew Point Temp Limit
ORH.S Outside Air RH Sensor
→
Configuration ECON
the minimum damper position.

Indoor Air Quality Options

DEMAND CONTROL VENTILATION — Under Configu-
→ →
ration IAQ DCV.C, the following configuration parame-
ters should be set to establish the minimum and maximum
points for outdoor air damper position during demand control
ventilation (DCV):
EC.MN Economizer Min.Position
IAQ.M IAQ Demand Vent Min.Pos.
→
Configuration IAQ
absolute minimum vent position (or maximum reset) under
DCV.
→
Configuration IAQ
minimum damper position (or with no DCV reset). This is also
referenced in the economizer section.
Exhaust Options —
ured with CV 2-stage PE or modulating PE. The following
exhaust options should be configured.
→ →
Configuration BP
Option) — For two-stage exhaust, under the Configuration
→
BP submenu, configure the following:
BP.P1 Power Exhaust On Setp.1
BP.P2 Power Exhaust On Setp.2
→ →
Configuration BP
Option) — For modulating exhaust, in the Configuration
BP submenu, configure the following:
BP.SP Building Pressure Set point
Set Clock on VFD (If Installed) —
mode is used for setting the date and time for the internal clock
of the VFD. In order to use the timer functions of the VFD
control, the internal clock must be set. The date is used to deter-
mine weekdays and is visible in the fault logs. Refer to the
VFD section in Appendix C on page 144 for information on
operating the VFD and using the keypad.
To set the clock, perform the following procedure from the
VFD keypad:
1. Select MENU (SOFT KEY 2). The Main menu will be
displayed.
2. Use the UP or DOWN keys to highlight CLOCK SET on
the display screen and press ENTER (SOFT KEY 2). The
clock set parameter list will be displayed.
28
Under the Configuration
→
EC.MN should always be set for
→ →
DCV.C IAQ.M is used to set the
→ →
DCV.C EC.MN is used to set the
The A series units can be config-
BF.CF=1 (Two-Stage
BF.CF=2 (Modulating Power Exhaust
The clock set
→
Exhaust
→