Carrier Weathermaster 48P2030-100, Controls, Start-Up, Operation, Service, And Troubleshooting, Page: 4 / 252

4
GENERAL
This book contains Start-Up, Controls, Operation, Trouble-
shooting and Service information for the 48/50P Series rooftop
units. See Table 1. These units are equipped with Comfort Link
controls version 7.X or higher. Use this guide in conjunction
with the separate installation instructions packaged with the
unit. Refer to the Wiring Diagrams literature for more detailed
wiring information.
The 48/50P Series units provide ventilation, cooling, and
heating (when equipped) in variable air volume (VAV) and
constant volume (CV) applications.
Table 1 — P Series Product Line
LEGEND
The 48/50P units contain the factory-installed Comfort Link
control system which provides full system management. The
main base board (MBB) stores hundreds of unit configuration
settings and 8 time of day schedules. The MBB also performs
self-diagnostic tests at unit start-up, monitors the operation of
the unit, and provides alarms and alert information. The system
also contains other optional boards that are connected to the
MBB through the Local Equipment Network (LEN). Informa-
tion on system operation and status is sent to the MBB proces-
sor by various sensors and the optional board located at the unit
and in the conditioned space. Access to the unit controls for
configuration, set point selection, schedule creation, and ser-
vice can be done through a unit-mounted scrolling marquee.
Access can also be done through the Carrier Comfort Net-
work ® using ComfortVIEW™ software, Network Service
Tool, or the accessory Navigator™ device.
The
Comfort Link system controls all aspects of the rooftop. It
controls the supply-fan motor, compressors, and economizers
to maintain the proper temperature conditions. The controls
also cycle condenser fans to maintain suitable head pressure.
All VAV units are equipped with a VFD (variable frequency
drive) for supply duct pressure control. The Comfort Link con-
trols can directly control the speed of the VFD based on a static
pressure sensor input. In addition, the Comfort Link controls
can adjust (but not control on CV and non-modulating power
exhaust units) the building pressure using multiple power ex-
haust fans controlled from damper position or from a building
pressure sensor. The control safeties are continuously moni-
tored to prevent the unit from operating under abnormal condi-
tions. Sensors include pressure transducers and thermistors.
A scheduling function, programmed by the user, controls the
unit occupied/unoccupied schedule. Up to 8 different schedules
can be programmed.
The controls also allow the service person to operate a service
test so that all the controlled components can be checked for
proper operation.
Conventions Used in This Manual
This manual will use the following conventions for discussing
configuration points for the local display (scrolling marquee or
Navigator™ accessory).
Parameter names will be written with the Mode name first,
then any submodes, then the parameter name, each separated
by an arrow symbol (

). Names will also be shown in bold
and italics. As an example, the IAQ Economizer Override Po-
sition which is located in the Configuration mode, Indoor Air
Quality Configuration sub-mode, and the Air Quality Set
Points sub-sub-mode, would be written as Configuration

IAQ

IAQ.SP

IQ.O.P .
This path name will show the user how to navigate through the
local display structure to reach the desired configuration. The
user would scroll through the modes and submodes using the
UP ARROW and DOWN ARROW keys. The arrow symbol in
the path name represents pressing ENTER to move into the
next level of the menu structure.
When a value is included as part of the path name, it will be
shown at the end of the path name after an equals sign. If the
value represents a configuration setting, an explanation will be
shown in parentheses after the value. As an example, Configu-
ration

IAQ

AQ.CF

IQ.A.C = 1 (IAQ Analog Input).
Pressing the ESCAPE and ENTER keys simultaneously will
scroll an expanded text description of the parameter name
across the display. The expanded description is shown in the
local display tables but will not be shown with the path names
in text.
The CCN (Carrier Comfort Network
®
) point names are also cross-
referenced in the local display tables (Appendix A) for users con-
figuring the unit with CCN software instead of the local display.
The CCN tables are located in Appendix B of this manual.
BASIC CONTROL USAGE
Comfort Link Controls
The Comfort Link controls are a comprehensive unit-management
system. The control system is easy to access, configure, diagnose
and troubleshoot.
The controls are flexible, providing constant volume and vari-
able air volume cooling control sequences, and heating control
sequences for two-stage electric and gas systems, multiple-
stage gas heating, and hydronic heat in both Occupied and Un-
occupied schedule modes. This control also manages:
• VAV duct pressure (through optional VFD), with configu-
rable static pressure reset
• Building pressure through four different power exhaust
schemes
• Return fan applications using fan tracking
• Condenser fan head pressure control
• Dehumidification (with optional reheat) and humidifier
sequences
• Space ventilation control, in Occupied and Unoccupied pe-
riods, using CO
2
sensors or external signals, with ventila-
tion defined by damper position or ventilation airflow
measurement
• Smoke control functions
• Occupancy schedules
UNIT
SIZE APPLICATION
48P2 All
Gas Heat
Vertical Supply/Return
CV ComfortLink Controls
48P3 All
Gas Heat
Vertical Supply/Return
VAV ComfortLink Controls
48P4 All
Gas Heat
Horizontal Supply/Return
CV ComfortLink Controls
48P5 All
Gas Heat
Horizontal Supply/Return
VAV ComfortLink Controls
50P2 All
Optional Electric Heat
Vertical Supply/Return
CV ComfortLink Controls
50P3 All
Optional Electric Heat
Vertical Supply/Return
VAV ComfortLink Controls
50P4 All
Optional Electric Heat
Horizontal Supply/Return
CV ComfortLink Controls
50P5 All
Optional Electric Heat
Horizontal Supply/Return
VAV ComfortLink Controls
CV — Constant Volume
VAV — Variable Air Volume