Hitachi Set Free mini-HNRQ1 Series, Service Manual

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INSTALLATION
3.9 Pressure Measurement
When the pressure is measured, it can be applied by the check joints as the following figures. Connect the
pressure gauge according to the table below, because of high pressure side and low pressure side change by
operation mode.
Item Cooling Operation Heating Operation
Check joint for gas stop valve “A” Low Pressure High Pressure
Check joint for piping “B” High Pressure Low Pressure
Check joint for liquid stop valve “C” High Pressure High Pressure
a) RAS-3.0~3.5HNBRKQ1 b) RAS-4.0~6.5HNBRKQ1 c) RAS-7.0~12HNBRMQ1
4. Electrical Wiring
●
Turn off the main power switch of the indoor unit and the outdoor unit, then wait for more than 10
minutes before electrical wiring work or a periodical check is performed.
●
Ensure that the indoor fan and the outdoor fan have been stopped before electrical wiring work or a
periodical check is performed.
●
Protect the wirings, electrical parts, and so on. from rats or other small animals. If not, rats may gnaw
at unprotected parts and which may lead to a fire.
●
Avoid the wirings touching the refrigerant pipes, plate edges and electrical parts inside the unit. If not, the
wirings will be damaged and a fire may be happened.
●
Secure the cables. External forces on the terminals can lead to a fire.
●
The indoor unit fan may continue to operate for up to five minutes following the heating cycle to dissipate
residual heat from the indoor unit.
WARNING
!
NOTICE