21
Table 29 — Air Quantity Limits (50A2,A3,A4,A5)
*Operation at these levels may be limited by entering evaporator air wet bulb temperatures.
CONTROLS QUICK START
The following section will provide a quick user guide to set-
ting up and configuring the A Series units with
Comfort
Link
controls. See Basic Control Usage section on page 4 for infor-
mation on operating the control. For wiring information, refer
to unit wiring diagrams in the Major System Components sec-
Variable Air Volume Units Using Return Air
Sensor or Space Temperature Sensor —
To con-
figure the unit, perform the following:
1. The type of control is configured under
Configuration
UNIT
C.TYP
. Set
C.TYP
to 1 (VAV-RAT) for return
air sensor. Set
C.TYP
to 2 (VAV-SPT) for space tempera-
ture sensor.
NOTE: For VAV with a space sensor (VAV-SPT), under
Configuration
UNIT
SENS
SPT.S
, enable the
space sensor by setting
SPT.S
to ENBL.
2. Install jumpers between R-W2 and W2-W1 on TB4 in
the control box.
3. The space temperature setpoints and the supply air set-
points are configured under the Setpoints menu. The
heating and cooling setpoints must be configured. See the
Heating Control and Cooling Control sections for further
description on these configurations. Configure the
following setpoints:
4. To program time schedules, make sure
SCH.N
=1 under
Configuration
CCN
SC.OV
SCH.N
to configure
the control to use local schedules.
5. Under the
Timeclock
SCH.L
submenu, enter the de-
sired schedule. See Time Clock Configuration section on
page 77 for further description of these configurations.
6. Under
Configuration
SP
SP.SP
, the supply duct
static pressure setpoint should be configured.
7. If supply air temperature reset is desired, under the
Configuration
EDT.R
submenu, the following set-
points should be configured:
NOTE: Configure either
RTIO
and
LIMT
or
RES.S
. All three
are not used.
8. See the Economizer Options section on page 22 for addi-
tional economizer option configurations.
9. See the Exhaust Options section on page 22 for additional
exhaust option configurations.
Multi-Stage Constant Volume Units with
Mechanical Thermostat —
To configure the unit, per-
form the following:
1. Under
Configuration
UNIT
C.TYP
, set
C.TYP
to 3
(TSTAT MULTI).
2. Remove jumpers from R-W2 and W2-W1 on TB4 in the
control box. Connect thermostat to TB4.
3. Under the
Setpoints
menu, set the following
configurations:
4. See the Economizer Options section on page 22 for
additional economizer option configurations.
5. See the Exhaust Options section on page 22 for additional
exhaust option configurations.
Multi-Stage Constant Volume Units with
Space Sensor —
To configure the unit, perform the
following:
1. Under
Configuration
UNIT
C.TYP
, set
C.TYP
to 5
(SPT MULTI).
UNIT
COOLING
ELECTRIC HEAT
Min CFM
Max CFM*
Min CFM
Max CFM
50A2,A3020
6,000
10,000
6,000
15,000
50A4,A5020
4,000
10,000
50A2,A3025
7,500
12,500
50A4,A5025
5,000
12,500
50A2,A4027
8,100
13,500
50A3,A5027
5,400
13,500
50A2,A4030
9,000
15,000
50A3,A5030
6,000
15,000
50A2,A4035
10,500
17,500
50A3,A5035
7,000
17,500
50A2,A4040
12,000
20,000
10,500
20,000
50A3,A5040
8,000
20,000
50A2,A4050
13,500
20,000
50A3,A5050
10,000
20,000
50A2,A4060
18,000
27,000
15,000
27,000
50A3,A5060
12,000
27,000
IMPORTANT: The
Comfort
Link controls provide the user
with numerous configuration options such as setpoints,
demand levels, reset, and many others. If the building
owner or design engineer has not provided specific recom-
mendations for these configuration settings, it is suggested
that the installer does not make changes to the default fac-
tory settings. The factory-configured default values are
appropriate for many applications.
IMPORTANT: The unit is shipped with the unit control
disabled. Enable the control by setting Local Machine
Disable (
Service Test
STOP
) to No.
OHSP
Occupied Heat Setpoint
OCSP
Occupied Cool Setpoint
UHSP
Unoccupied Heat Setpoint
V.C.ON
VAV Occupied Cool On Delta
V.C.OF
VAV Occupied Cool Off Delta
SASP
Supply Air Setpoint
SP.SP
Static Pressure Setpoint
RS.CF
EDT Reset Configuration
RTIO
Reset Ratio (if
RS.CF
= 1 or 2)
LIMT
Reset Limit (if
RS.CF
= 1 or 2)
RES.S
EDT 4-20 mA Reset Input (if
RS.CF
= 3)
SA.HI
Supply Air Setpoint Hi
SA.LO
Supply Air Setpoint Lo
Summary of Contents for Carrier Weathermaker 48A2
Page 105: ...105 Fig 20 Typical Main Control Box Wiring Schematic 48 50A2 A3 A4 A5 Units...
Page 106: ...106 Fig 21 Typical Auxiliary Control Box Wiring Schematic...
Page 107: ...107 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown a48 8357...
Page 108: ...108 TO NEXT PAGE Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown A48 7296...
Page 109: ...109 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont A48 8358...
Page 110: ...110 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown a50 8228...
Page 111: ...111 Fig 25 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown...
Page 112: ...112 Fig 26 Typical Low Ambient Controls Option Wiring...
Page 113: ...113 Fig 27 Typical Small Chassis Component Location Size 020 035 Units...
Page 114: ...114 Fig 28 Typical Large Chassis Component Locations Size 040 060 Units...
Page 118: ...118 Fig 30 Economizer Control Board ECB1 and VAV Control Board ECB2 A48 7706...
Page 142: ...142 A48 3733 Fig 56 Main Burner Removal...
Page 176: ...176 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716...
