Reading The Operating Machine State - Trane UniTrane Installation Operation & Maintenance

Table 40. Blink Sequence Corresponding Diagnostic Codes
Sequence 1 Sequence 2
1 2 3 4 1 2
Reading the
Operating
Machine State
102
Sequence 3
3 4 1 2 3 4
Use the human interface to read the unit operating machine state.
1. Read and record the initial TUC address.
2. Set the TUC DIP switch #5 and #8 to ON (address = 9). The
remaining switches will be off.
3. Short and hold the test input.
4. The LEDs will blink to define an operating machine state. The
operating machine state information will be displayed in a series
of three blink sequences.
Sequence 1: When the test input is shorted continuously all
LEDs go off for one second.
Sequence 2: LED #5 will light to indicate that sequence 2 is
currently being displayed. LEDs one through four will display the
first part of the operating machine state.
Sequence 3: LED #6 will light to indicate that sequence 3 is
currently being displayed. LEDs one through four will display the
second part of the operating machine state.
5. Reference Table 25 on page 75 to interpret the operating machine
state derived from the blink sequences.
Terminal Unit
Control (TUC)
Code Diagnostic
None Power failure
None Controller failure
00 None
8B Condensate overflow
9B Leaving water temp
sensor 1 failure
A0 Zone and supply temp
sensor failure
C8 High EWT
CB Low EWT
CF Low temp. detect. or
condensate overflow
D3 Low discharge air temp
D4 Smoke alarm
D5 High dischg air temp
DD Low fresh air temp
F8 Bad configuration
FE Return air high limit
Latch
None
None
N/A
Yes
No
No
No
No
Yes
Yes
Yes/No
Yes/No
No
No
Yes
UNT-IOM-6