Trane RT-SVX38C-EN, Installation, Operation And Maintenance Manual

Page: 41 / 48

Troubleshooting
RT-SVX38C-EN 41
Method 3
To test LEDs with ZSM connected to unit, test voltages at
LED terminals on ZSM. A measurement of 32 VDC, across
an unlit LED, means the LED has failed.
Programmable and Digital Zone Sensor
Test
Testing serial communication voltage
1. Verify 24 VAC is present between terminals J6-14 and
J6-11.
2. Disconnect wires from J6-11 and J6-12. Measure the
voltage between J6-11 and J6-12; it should be about 32
VDC.
3. Reconnect wires to terminals J6-11 and J6-12. Measure
voltage again between J6-11 and J6-12; voltage should
flash high and low every 0.5 seconds. The voltage on
the low end will measure about 19 VDC, while the
voltage on the high end will measure from
approximately 24 to 38 VDC.
4. Verify all modes of operation, by running the unit
through all of the steps in the “Test Modes” section
discussed in “Unit Start-Up”.
5. After verifying proper unit operation, exit the test
mode. Turn on the fan continuously at the ZSM, by
pressing the button with the fan symbol. If the fan
comes on and runs continuously, the ZSM is good. If
you are not able to turn on the fan, the ZSM is
defective.
ReliaTel™ Refrigeration Module (RTRM)
Default Chart
If the RTCI loses input from the building management
system, the RTRM will control in the default mode after
approximately 15 minutes. If the RTRM loses the Heating
and Cooling setpoint input, the RTRM will control in the
default mode instantaneously. The temperature sensing
thermistor in the Zone Sensor Module is the only
component required for the “Default Mode” to operate.
Unit Operation without a Zone Sensor
This procedure is for temporary operation only. The
economizer and condenser fan cycling functions are
disabled.
1. Open and lock the unit disconnect switch.
2. Remove the Outside Air Sensor (OAS) from the
condenser section of unit.
3. Use 2 wire nuts to individually cap the wires.
4. Locate the RTRM (J6). Connect 2 wires to terminals
J6-1 and 2.
5. Connect the sensor (OAS) using two wire nuts to the 2
field-supplied wires that were connected to terminals
1 and 2 on J6.
Unit Economizer Control (ECA)
Troubleshooting
ReliaTel Control
Verify economizer status by economizer actuator (ECA)
LED indicator:
Heating Failure
Verify heat failure by ignition module (IGN) LED indicator:
Cooling Failure
• Cooling and heating set point (slide pot) on the
thermostat has failed.
• CC1 or CC2 24 VAC control circuit has opened, check
CC1 and CC2 coils, and any of the controls below that
apply to the unit (HPC1, HPC2, LPC1, LPC2, Frostat™).
WARNING
Hazardous Voltage!
Disconnect all electric power, including remote
disconnects before servicing. Follow proper lockout/
tagout procedures to ensure the power can not be
inadvertently energized. Failure to disconnect power
before servicing could result in death or serious injury.
Off No power or power failure
On Normal, OK to economize
Slow flash Normal, not OK to economize
Fast flash
½ sec on/2 sec off Communications failure
Pulse flash
2 sec on/½ sec off 1 flash Actuator fault
2 flashes CO
2
sensor
3 flashes RA humidity sensor
4 flashes RA temp sensor
5 flashes OA quality sensor
6 flashes OA humidity sensor
7 flashes OA temp sensor
8 flashes MA temp sensor
9 flashes RAM fault
10 flashes ROM fault
11 flashes EEPROM fault
Off No power or power failure
On Normal
Slow flash Normal, heat call
Fast flash 1 flash No communication
2 flashes System lockout
3 flashes Pressure switch fail
4 flashes TC01 or TC02 open
5 flashes Flame w/o gas valve
6 flashes Flame rollout open