Trane IntelliPak I Programming, Troubleshooting Manual page 133

DIAGNOSTIC DISPLAYED
Improper Airflow for
Dehumidification
Problem: The unit
transitioned into
Dehumidification mode during
occupied mode and the IGV/
VFD output did not reach 80%
within the designated timeout
period after the transition.
Check: Wiring from the VAV
Box Drive Open relay to VAV
Boxes or check that the VAV
Box Drive Open relay on the
RTM is energizing during
Dehumid mode. If VAV Boxes
are driving open in response
to the command check that
the Supply Air Pressure
sensed decreases and the
IGV/VFD output signal from
the RTM is increasing to
compensate. Also check that
the supply air pressure sensor
is valid and no diagnostic
conditions exist related to
Supply Air Static Pressure
control.
Leaving Recovery Exhaust
Temp Failure
Problem: The Leaving
Recovery Exhaust Temp is out
of range.
Check wiring from MPM to
sensor. If wiring is correct
check voltgae on sensor input.
LonTalk Communications
Interface (LCI) Module
RT-SVP04F-EN
REASON FOR DIAGNOSTIC
IGV/VFD control output did
not increase above 80% within
the VAV Box Drive Open stroke
time + 5 minutes. The supply
air static pressure control
function remains active
through a transition into
Dehumidification and the VAV
Box Drive Open signal is set
during Dehumid mode.
Dehumidification mode
requires unit to be at full
airflow for proper
performance.
Leaving Recovery Exhaust
Temperature signal input
voltage is out of normal range
(< -55 F or > 209 F)
• None
System Testing & Troubleshooting
UCM'S REACTION
The Dehumidification function
is disabled
Exhaust Air Bypass Damper
modulated fully closed if
energy recovery for heating is
active or if energy recovery is
not active. If OA Damper is
fully open Exhaust Air Bypass
and Outside Air Bypass
dampers modulated fully open
when Outside Air Temp is 10F
or less.
• None
RESET REQUIRED
(PMR) A manual reset is
required
anytime after the Diagnostic is
set to re-enable
Dehumidification control. The
Diagnostic can be reset by the
Human Interface or Tracer, or
by cycling power to the RTM.
(PAR) An automatic reset
occurs after the Leaving
Recovery Exhaust Temp input
returns to within range
continupusly for 10 seconds
• None
133