Trouble Shooting
RT-SVX38B-EN
41
Test 4 - LED Indicator Test, (SYS ON, HEAT,
COOL & SERVICE)
Method 1
Testing the LED using a meter with diode test function.Test
both forward and reverse bias. Forward bias should
measure a voltage drop of 1.5 to 2.5 volts, depending on
your meter. Reverse bias will show an Over Load, or open
circuit indication if LED is functional.
Method 2
Testing the LED with an analog Ohmmeter. Connect
Ohmmeter across LED in one direction, then reverse the
leads for the opposite direction. The LED should have at
least 100 times more resistance in reverse direction, as
compared with the forward direction. If high resistance in
both directions, LED is open. If low in both directions, LED
is shorted.
Method 3
To test LED’s 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 & Digital Zone Sensor Test
Testing serial communication voltage
1. Verify 24 VAC is present between terminals J6-14 & J6-
11.
2. Disconnect wires from J6-11 and J6-12. Measure the
voltage between J6-11 and J6-12, 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 the fan on 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 the fan on, 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 two (2) wire nuts, to individually cap the wires.
4. Locate the RTRM (J6). Connect two (2) wires to
terminals J6-1 and 2.
5. Connect the sensor (OAS) using two wire nuts to the
two (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:
OFF: No Power or Failure
ON: Normal, OK to Economize
Slow Flash: Normal, Not OK to Economize
Fast Flash - 1/2 Second On / 2 Seconds Off:
Error Code:
Communications Failure
Pulse Flash:2 Seconds On / 1/2 Second Off:
Error Code:
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
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.
