Toshiba MD-VNK802HEXE Service Manual page 36

Indoor unit operation checking function (of the indoor unit)
This function allows you to check the operations using the indoor unit only without communicating with the remote
controller or outdoor unit. This function is available even while the system is running or stopped.
However, if it is used for a long period of time, a malfunction may occur. Use this function for several minutes as
an approximate guide.
[Procedure]
1
Short circuit the CHK pin (CN71 on the indoor circuit board). The operation mode varies
depending on the indoor unit status.
Normal ... Both the float SW and fan motor are normal.
Abnormal ... The float SW or fan motor is abnormal.
2
Only when normal, the opening can be minimum (30 pls) only for the indoor PMV if you short
circuit the DISP pin (CN72 on the indoor circuit board) while the CHK pin (CN71 on the indoor
circuit board) is short circuited. If you open the DISP pin, the opening will be maximum (1500 pls)
again.
[Releasing]
Open the CHK pin. While the system is running, it stops temporarily but resumes automatically in several minutes.
DISP pin opened
Fan motor High (H)
PMV (*) Max. opening (1500 pls)
Drain pump ON
Humidifier OFF
Communication All ignored
P.C. board LED Lights up
* When replacing the PMV coil, apply the maximum opening.
* For the detailed positions of CHK pin (CN71 on P.C. board) and DISP pin (CN72 on P.C. board), refer to the
Indoor Printed Circuit Board MCC-1615 on page 32.
Indoor unit exhibition mode (of the indoor unit)
This function can be used when you use the indoor unit and remote controller only in an exhibition, etc. The group
operation is also available.
[Procedure]
1
Short circuit the DISP pin (CN72 on the indoor circuit board). This function is not available if the
CHK pin (CN71 on the indoor circuit board) is short circuited earlier.
2
To perform the group operation, configure the group setting in the same way as in normal.
3
All the sensor error judgments and communications with the outdoor unit are disabled during
DISP pin short circuit. The opening of PMV is always the maximum (1500 pls).
[Releasing]
Open the DISP pin.
CHK pin short circuit
Normal
DISP pin short circuited
High (H)
Min. opening (30 pls)
ON
OFF
All ignored
Lights up
34
Abnormal
Stop
Min. opening (30 pls)
ON
OFF
All ignored
Blinks