Main Concerns For Commissioning - Hitachi UTOPIA R32 Series Installation And Operation Manual

8.1 Main concerns for commissioning

When installation is completed, perform test run according to the following procedure, and hand
over the system to the customer. Perform test run regarding indoor units one by one in order, and
confirm that the electrical wiring and the refrigerant piping are correctly connected.
!
CAUTION
Do not operate the system until all the check points have been cleared:
• Check to ensure that the electrical resistance is more than 1 MΩ, by measuring the resistance
between ground and the terminal of the electrical parts. If not, do not operate the system until
the electrical leakage is found and repaired. Do not impress the voltage on the terminals for
transmission 1 and 2.
• Check to ensure that the stop valves of the outdoor unit are fully opened, and then start the
system.
• Check to ensure that the switch on the main power source has been ON for more than 12 hours,
to warm the compressor oil by the oil heater.
Pay attention to the following items while the system is running:
• Do not touch any of the parts by hand at the discharge gas side, since the compressor chamber
and the pipes at the discharge side are heated higher than 90°C.
• DO NOT PUSH THE BUTTON OF THE MAGNETIC SWITCH(ES), it will cause a serious accident.
• Do not touch any electrical components for more than three minutes after turning OFF the main
switch.
• Confirm that the gas line stop valve and the liquid line stop valve are fully open.
• Confirm that the leakage of the refrigerant does not exist. The flare nuts are sometimes
loosened by vibration during transportation.
• Check that the refrigerant piping and the electrical wiring conform to the same system.
• Confirm that the DIP switch setting on the printed circuit board of the indoor units and the
outdoor units are correct.
• Check whether or not the electrical wiring of the indoor units and the outdoor units are
connected as shown in the chapter
!
CAUTION
Confirm that field-supplied electrical components (main switch fuse, fuse-free breaker, earth
leakage breakers, wires, conduit connectors and wire terminals) have been properly selected
according to the electrical data given in the Technical Catalog of the unit and ensure that the
components comply with national and local codes.

NOTE
• For 2 indoor units system check the indoor unit outlet air temperature at test run. If the
temperature difference is large, approximately: 10 deg. or more (in cooling mode); 20 deg. or
more (in heating mode), recheck the refrigerant piping, installation may have some problem.
PMEN0654 rev.0 - 12/2023
"DIP switches".
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