Toshiba HFC R407C Service Manual page 32

The combination of the display switch and the four 7-segment LEDs (LD 101-LD 104) indicates the
diagnostic details.
7 segment LED display
Switch Indication LD 101LD 102 LD 103
position
0 Serial - - -
signal
1 Fault [E] - Fault code display (normal [00]). Refer to fault code section for details.
codes
2 Frequency Instructed demand frequency of cooling or heating [00 - 1F].
instructions Refer to the Multi Controller display conversion table (1) for display switch position "2"
to the out-
door unit
3 Oil - - -
retrieval,
superheat
control
Defrost Displays [dF] during defrost operation
4 Operation M/C operating Outdoor unit operating mode: Heating [H-], Cooling [-C], Simultaneous Heating [Hc],
mode mode: Simultaneous Cooling [hC], Stop [--], Defrost [J-]
Heating [H-],
Cooling [C-]*
5 Restart - - -
timer
6 Circuit test [c] [k] Displays unit being tested [A b C d]
7 PMV A [P] [A] Displays the degree of PMV opening (0-240) as a hexadecimal code:
8 PMV B [P] [b] [00]: Closed, [FO]: Fully open
9 PMV C [P] [c]
10 PMV D [P] [d]
11 ThA [h] [A] Displays sensor temperature
12 ThB [h] [b] Refer to the Multi Controller sensor temperature conversion table (1).
13 ThC [h] [c]
14 ThD [h] [d]
15 ThX [h] [H]
* and Simultaneous Cooling/Heating [HC], Defrost [J-]
32
Diagnostic procedure
Multi Controller
MCC - 1223
Unit B
Unit A Unit C
Capacity rank switches
Multi Controller control board
Receiving Sending - Sending
from to to
unit B unit B unit A
Oil Superheat - Superheat Oil
retrieval control control
unit B unit B unit A
7-segment LED
LD 102 LD 104
LD 101 LD 103
Unit D
Display switch
LD 104
Receiving Receiving - Receiving Sending
from from from
unit A oudoor unit D
unit
- - Oil
retrieval retrieval
unit A unit D
Normal display [0], Restart timer counting [1]
Indicates faulty unit connection [A b C d]
- Sending Receiving Sending
to to from
unit D unit C unit C
Superheat - Superheat Oil
control control retrieval
unit D unit C unit C
to
outdoor
unit
-