Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 159

4.5.6 Test run and handling instruction
(1) Inspection
Check according to the following check items.
(2) Test run
(1) Conduct the test run after turning on the power for 20 minutes.
(Run electricity for 20 minutes with a hot stand-by to prevent compression of the compressor liquid.)
(2) If the compressor does not operate after the operation has started, wait for 5 ~ 10 minutes.
(This may be due to a delayed start.)
(3) Carry out the test run for each unit individually. (If 2 or 3 units are tested at the same time, wrong wiring and wrong pipe
connections cannot be checked.)
(4) After each individual test, run the units in all the rooms simultaneously and check the units.
(5) Test both the cooler and the heater.
(Three-minute restart preventive timer)
When the air conditioner is restarted or when changing the operation, the unit will not start operating for approximately 3
minutes. This is to protect the unit and it is not a malfunction.
Installation test check points
Check the following points again after completion of the installation, and before turning on the power. Conduct a test
run again and ensure that the unit operates properly. At the same time, explain to the customer how to use the unit and
how to take care of the unit following the instruction manual.
After installation
□ The power supply voltage is correct as the rating.
□ No gas leaks from the joints of the service valve.
□ Power cables and crossover wires are securely inserted and fixed
to the terminal board.
□ Each indoor and outdoor unit is properly connected (no wrong
wiring or piping).
□ Service valve is fully open.
□ Refrigerant has been additionally charged (when the total pipe
length exceeds the refrigerant charged pipe length).
□ The pipe joints for indoor and outdoor pipes have been insulated.
□ Earthing work has been conducted properly.
Beware of wrong connections in refrigerant piping and wiring
● Make sure to match the piping and wiring from each unit to the outdoor unit.
● Be careful because if connections are wrong, normal operation cannot be achieved and may damage the compressor.
Indoor unit
[Correct connections]
A unit
A
B unit
B Outdoor
unit
C
C unit
D
D unit
Test run
□ Air conditioning and heating are normal.
□ No abnormal noise.
□ Water drains smoothly.
□ Protective functions are not working.
□ Operation of the unit has been explained
to the customer.
[Example of wrong connections]
Piping
Wiring
Indoor unit
A unit
A
B unit
B
C
C unit
D
D unit
SCM-HG (4 room)
Outdoor
unit
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