Trane IntelliPak I - Page 136

136 RT-SVP04F-EN
System Testing & Troubleshooting
MPM Communications
Failure
Problem: RTM lost
communication to the MPM
module.
Check wiring between the
MPM and RTM. Check for
properly powered MPM board.
MPM Communications Failure.
The RTM lost communications
to the MPM for 60 seconds.
MPM Communication Failure.
All active commands and
SETPOINTs provided by the
MPM module will be canceled
and/or ignored. Return Fan
control function is disabled.
For evaporative Condensing
units, a lockout request is
issued, for all circuits, to the
compressors Staging Control
Function.
(PAR) An automatic reset
occurs after one complete set
of the required IPC packets
has been received.
NSB Panel Zone Temp
Sensor Failure
Problem: The NSB panel's
zone temp sensor input is out
of range. (This input is at the
NSB Panel, not on the Rooftop
unit itself).
Check: If have an external
sensor connected to the NSB
Panel Zone Sensor input, then
the internal NSB Panel zone
sensor should be disabled.
Verify sensor resistance. If in
valid range, check wiring
between Sensor and NSB
Panel.
NSB Panel Communication
Failure
Problem: The RTM has lost
communications with the
Night SetBack Panel
(programmable zone sensor).
Check: Field/unit wiring
between RTM and NSB Panel.
The RTM has lost
communications with the NSB
panel.
The unit reverts to the next
lower priority mode switching
source (typically the HI default
mode). If the NSB Panel Zone
Sensor is the designated
sensor source for any
functions, those functions are
disabled.
(PAR) An automatic reset
occurs after communication
has been restored.
OA Humidity Sensor Failure
Problem: The Outside Air
Humidity sensor data is out of
range.
Check: Check field/unit wiring
between Sensor and RTM.
The unit is reading a signal
that is out of range for the
Outside Air humidity sensor
(Humidity < 5% or Humidity >
100%).
The Economizer Enable r.e
Enthalpy function reverts to
Dry-Bulb Temperature
changeover (“Level 1”)
control.
(PAR) An automatic reset
occurs after the OA Humidity
input returns to its allowable
range for 10 seconds.
DIAGNOSTIC DISPLAYED REASON FOR DIAGNOSTIC UCM’S REACTION RESET REQUIRED