Start- -Up; Additional Installation/Inspection; Service Test; Fan Test - Carrier 48/50HC04---14 Controls, Start-Up, Operation And Troubleshooting Instructions

START- -UP

IMPORTANT: Follow the base unit's start-up sequence
documented in its specific instructions.
unit's start-up check list when performing the start-up. At
the end of this manual there is an additional RTU-OPEN
Start-up Sheet to be completed and included with the base
unit check list.
Besides the base unit start-up, there are a few steps to take
to properly start-up the controls. RTU-OPEN's Service
Test function should be used to assist in the base unit
start-up and also allows verification of output operation.
Controller configuration is also part of start-up. This is
especially important when field accessories have been
added to the unit. The factory pre-configures options
installed at the factory. There may also be additional
installation steps or inspection required during the start-up
process.

Additional Installation/Inspection

Inspect the field installed accessories for proper
installation, making note of which ones do or do not
require configuration changes. Inspect the RTU-OPEN's
Alarms for initial insight to any potential issues. See
troubleshooting section for alarms.
sensor for relocation as intended during installation.
Inspect special wiring as directed below.
Humidi- -MiZert Control Wiring
In units equipped with the optional Humidi-MiZer option
there are 2 pink wires loose in the control box used to
control the dehumidification function of the unit. These
pink wires are meant to be ties to a space humidistat or
thermidistat on an electromechanical
RTU-OPEN equipped units these pink wires must be
connected to J11-7 & 8 to allow the OPEN board to
operate the dehumidification function or the unit.
Disconnect the J11 Phoenix style connector form the
board and use the plug screws to secure the pink wires in
pins 7 and 8, reconnect the plug to the board at J11.
Power Exhaust Relay Power
The relay used by the RTU-OPEN board to control power
exhaust is a dry contact which means it does not have
24vac. This 24vac must be connected to the relay to
allow it operate the power exhaust relay in the PE
accessory. A 24vac source should be provided to the
J11-2 pin on the RTU-OPEN. This can be provided by the
unit's transformer from various sources. The "R" terminal
on the unit's low voltage terminal board (LVTB) is a
logical source.

Service Test

The Service Test function can be used to verify proper
operation of compressors, heating stages, indoor fan,
power exhaust fans, economizer, and dehumidification.
Use of Service Test is recommended at initial system start
up and during troubleshooting. See Appendix A for
Service Test Mode table.
Service Test mode has the following changes from normal
operation:
S Outdoor air temperature limits for cooling circuits,
Use the base
economizer, and heating are ignored.
S Normal compressor time guards and other staging
delays are ignored.
S The status of Alarms (except Fire and Safety chain) is
ignored, but all alerts and alarms are still broadcasted
on the network.
Service Test can be turned ON/OFF at the unit display or
from the network. Once turned ON, other entries may be
made with the display or through the network. To turn
Service Test on, change the value of Test Mode to ON, to
turn Service Test off, change the value of Test Mode to
OFF.
NOTE: Service Test mode is password protected when
accessing from the display. Depending on the unit model,
factory- - installed options, and field- - installed accessories,
some of the Service Test functions may not apply.

Fan Test

This point allows the board's fan output to be manually
turned On (Enable) and Off (Disable). Other test points
Inspect the SAT
that require the fan for operation will automatically turn
the fan on and this point will still show "Disable." Fan
test can operate simultaneously with other Service Test
Points.

Compressor 1 and Compressor 2 Test

The compressor test points are used to change output
status for the individual compressors. Compressor starts
are not staggered. The fan and heating service test outputs
unit. On
are reset to "Disable" for the compressor service tests.
The Indoor fan and outdoor fans are controlled normally
to maintain proper unit operation. All normal cooling
alarms and alerts are functional.
NOTE:
Compressor 2 due to outdoor fan control on Compressor
1. Always test Compressor 1 first, and leave it on to test
Compressor 2.

Heat 1 and Heat 2 Test

The heat test points are used to change output status for
the individual heat stages, gas or electric. The fans and
cooling service test outputs are reset to "Disable" for the
heat service tests. Indoor and outdoor fans are controlled
normally to maintain proper unit operation. All normal
heating alarms and alerts are functional.

Reversing Valve Test

This test point activates the DO7 relay at J11. These
rooftop units do not use reversing valve control for heat
pumps, therefore this test is not used.
13
Compressor 1 is always operated with