Trane IntelliPak SCRF 25, Installation, Operation And Maintenance Manual

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112 SCXF-SVX01Q-EN
Category Diagnostic
Unit HI Communications Failure
Problem
The RTM has lost communication with the unit mounted (local) human interface (HI).
Check
Field/unit wiring between RTM hand local HI.
Reason for
Diagnostic
The RTM has lost communication with the unit-mounted human interface.
Controls
Reaction
A fail-safe function in the HI will cause the following sequence:
1. Disallow any interaction between the HI and the RTM (or any other modules)
2. Render all HI keystrokes ineffective
3. Cause the following message to display on the unit-mounted HI display: “Local HI communications loss. Check comm link
wiring between modules.” If the unit has a remote HI option, then this diagnostic will display as any other automatic reset
diagnostic.
Reset
Required
(INFO) An automatic reset occurs after communication is restored between the RTM and the HI. When the failure screen clears,
the general display restores to allow the HI to interact with the RTM again.
Unoccupied Zone Cool Setpoint Failure
Problem
The unoccupied zone cooling setpoint input is out of range.
Reason for
Diagnostic
The input designated as the unoccupied zone cooling setpoint source is out of range (temp < 45°F or temp > 94°F).
Controls
Reaction
The active unoccupied zone cooling setpoint reverts to the default value.
Reset
Required
(PAR) An automatic reset occurs after the designated unoccupied zone cool setpoint input returns to its allowable range for 10
continuous seconds, or after the user defines a different, valid unoccupied zone cool setpoint selection source.
Unoccupied Zone Heat Setpoint Failure
Problem
The unoccupied zone heating setpoint input is out of range.
Reason for
Diagnostic
The input designated as unoccupied zone heating setpoint source is out of range (temp < 45 F or temp > 94 F).
Controls
Reaction
The active unoccupied zone heating setpoint reverts to the default value.
Reset
Required
(PAR) An automatic reset occurs after the designated unoccupied zone heat setpoint input returns to its allowable range for 10
continuous seconds, or after the user defines a different, valid unoccupied zone heating setpoint selection source.
V
VCM Communication Failure
Problem The RTM has lost communication with the VCM.
Verify Check field/unit wiring between RTM and VCM.
Reason for
Diagnostic
RTM has lost communication with VCM.
Controls
Reaction
All active commands and setpoints provided by the VCM are canceled and/or ignored. A fail-safe function in the VCM will cause
all outputs to de-energize and/or set to zero. The outside air damper minimum position function will revert to using the O/A
flow compensation function if O/A flow compensation is enabled or set to the default minimum position function if O/A flow
compensation is disabled or not available.
Reset
Required
(PAR) An automatic reset occurs after communication is restored.
Velocity Pressure Sensor Failure
Problem
The velocity pressure input signal is out of range.
Check
Check field/unit wiring between sensor and VCM.
Reason for
Diagnostic The unit is reading a signal that is out of range for the velocity pressure transducer input (during calibration: V < 40 mV or V >
420 mV, during operation: V < 40 mV or V > 0.75 V).
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