Emergency Operation - Toshiba MMU-P0121H Service Manual

3-8. EMERGENCY OPERATION

3-8-1. Emergency Operation in Failure of Pressure Sensor or
Temperature Sensor
This air conditioner does not correspond to the backup operation function when each sensor has failed.
When a fault is judged as one of sensors, use "Emergency operation when outdoor unit" has failed.
3-8-2. Emergency Operation When One Compressor has Failed
(Emergency Operation in Compressor Trouble)
<Outline>
When one of two compressors installed to the outdoor unit fails, take the following action if emergency operation
by other normal compressor is necessary.
* NOTE 1 : In the case of single compressor installed unit (6HP), backup operation by one compressor is
unavailable. In this time, use "Emergency operation when outdoor unit failed".
* NOTE 2 : For the emergency operation when the failed compressor is an inverter, the capacity control is
performed by ON/OFF control of fixed-speed compressor.
NOTE 3 : When motor winding of the compressor fails (Short, etc.), do not set backup of the compressor
*
because deterioration of oil is great.
(Another error on the outdoor unit may be caused.)
<Work procedure>
(1) First, turn off the power supply of all the outdoor units which are connected to the system.
(2) The following works are performed to the outdoor unit of which the compressor failed.
According to the following table, set DIP switch (SW06) on the interface P.C. board.
Initial set up at shipment from factory
No.1 compressor (Compressor at left of front side) has failed
No.2 compressor (Compressor at right of front side) has failed
(3) Then, backup set up is complete. Turn on the power supply of all the outdoor units.
<Table Switch set up in compressor backup>
3-131
SW06
Bit 1 Bit 2
OFF OFF
ON OFF
OFF ON
Bit 3 Bit 4
OFF OFF
OFF OFF
OFF OFF