Indoor Fan Operation Check Function; Indoor Fan Only Operating Mode - Toshiba Super MMU-AP0091H Service Manual

8-7-11. Indoor Fan Operation Check Function

This function is provided to check operation of single indoor unit without using communication with the remote
controller or outdoor unit. This function can be used regardless operating or stopping of the system.
However, if this function is used for a long time, a trouble of the air conditioner may be caused. Therefore using
of this function should be restricted to several minutes.
[Operation]
1. Short-circuit CHK pin (CN71 on the indoor P.C. board).
If short-circuiting DISP pin (CN72 on the indoor P .C. board) while short-circuiting CHK pin (CN71 on the
indoor P .C. board), the indoor PMV only becomes the minimum opening (30 pulse). When opening DISP pin,
it becomes the maximum opening again.
[Clear]
Open CHK pin. If the system is operating, it stops once but automatically restart after several minutes.
∗ For the details of CHK pin (CN71 on indoor P .C. board) and DISP pin (CN72 on indoor P .C. board), refer to
11. Control circuit configuration, Indoor unit 2, Indoor P.C. board MCC-1402 and MCC-1403.

8-7-12. Indoor Fan Only Operating Mode

When operating an air conditioner with indoor units and remote controller only in fan operation etc., this function
can be used. A group operation is also available.
[Operation]
1) Short circuit DISP pin (CN72 on the indoor P .C. board). However, if CHK pin (CN71 on the indoor P .C. board)
has been previously short circuited, this function is unavailable.
2) In a group operation, set up a group as usual.
3) While DISP pin is short circuited, all the sensor error judgment operation and communication with the outdoor
unit are not performed. PMV is fixed to the Max. opening.
[Clear]
Open DISP pin.
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