Toshiba MMU-AP0091H service manual Setup for header unit, 194

[Setup for header unit]

9.The low pressure (Ps) data is displayed on the 7-segment display.

Slowly close the service valve of the gas pipe and adjust so that a pressure of 0.12 MPa is displayed.

10.When the manifold gauge pressure of the malfunctioning outdoor unit is almost the same as that of the header unit in which the pressure adjustment has been made, fully close the service valve of the gas pipe in the header unit.

[Set up the malfunctioning outdoor unit as follows]

11.When the manifold gauge pressure of the malfunctioning outdoor unit becomes below 0.1 MPa, fully close the packed valve of the balance pipe and then push SW05 on the interface P.C. board to finish the pump down operation.

12.Turn off the power supplies of all of the outdoor units, and use a refrigerant recovery device to recover the remaining refrigerant in the outdoor unit, in which the pump down operation has been completed.

Be sure to measure the recovered refrigerant, as the same amount of refrigerant will be required to be re- charged after the repair.

8

Fully close the balance pipes of the outdoor units other than the master unit and the malfunctioning unit.

6

Fully close the service valve of the gas pipe approx. 10 minutes after the system has started.

Outdoor unit with trouble

7

The header unit is selected as the outdoor unit for pressure adjustment.

11

When the low pressure of the malfunctioning outdoor unit is below

0.10MPa, fully close the service valve of the balance pipe. Push the switch SW05 to finish the pump-down operation.

10

Turn off the main power supplies of all the outdoor units.

Using a recovery device, recover the remaining refrigerant in the outdoor unit in which pump-down operation has finished and measure the amount.

9

Close service valve of the gas pipe while checking the low pressure, and then adjust the pressure to 0.12 MPa.

12

When the pressure of the malfunctioning outdoor unit (manifold gauge) and pressure of the header unit become almost same, close valve of the gas pipe fully.

Return all SW01/02/03 of the header unit to (1/1/1) to complete the work.

194