Hitachi 3HRNM1Q, Installation & Maintenance Manual

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DSW1-1ON
5.7 Collecting Refrigerant
When the refrigerant should be collected into the
outdoor unit due to indoor/outdoor unit relocation,
collect the refrigerant as follows.
(1) Attach the manifold gauge to the gas stop
valve and the liquid stop valve.
(2) Turn ON the power source.
(3) Set the DSW1-1 pin of the outdoor unit
PCB at the “ON” side for cooling operation.
Close the liquid stop valve and collect the
refrigerant.
(4) When the pressure at lower pressure side
(gas stop valve) indicates -0.01MPa
(684mmHg), perform the following
procedures immediately.
* Close the gas stop valve.
* Set the DSW1-1 pin at the “OFF” side.
(To stop the unit operation.)
(5) Turn OFF the power source.
Dip Switch
Manifold Gauge
Liquid
Stop Valve
Gas Stop Valve
6. Electrical Wiring
6.1 General Check
(1) Make sure that the field-selected electrical
components (main power switches, circuit
breakers, wires, conduit connectors and
wire terminals) have been properly
selected according to the electrical data.
Make sure that the components comply
with National Electrical Code (NEC).
(2) Check to ensure that the voltage of power
supply is 6% of nominal voltage
and earth phase is contained in the power
supply wires. If not, electrical parts will be
damaged.
(3) Check to ensure that the capacity of power
supply is enough.
If not, the compressor will be not able to
operate because of abnormal voltage drop
at starting.
(4) Check to ensure that the earth wire is
connected.
(5) Check to ensure that the electrical
resistance is more than 1 megohm, 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.
NOTE
Fix the rubber bushes with adhesive when
conduit tubes to the outdoor unit are not used.
Turn OFF the main power switch to the
indoor unit and the outdoor unit and wait for
more than 1 minute before electrical wiring
work or a periodical check is performed.
Check to ensure that the indoor fan and the
outdoor fan have stopped before electrical
wiring work or a periodical check is
performed.
Protect the wires, electrical parts, etc. from
rats or other small animals.
If not protected, rats may gnaw at
unprotected parts and at the worst, a fire
will occur.
Avoid the wirings from touching the
refrigerant pipes, plate edges and electrical
parts inside the unit.
If not do, the wires will be damaged and at
the worst, a fire will occur.
Tightly secure the power source wiring
using the cord clamp inside the unit.
17
may be faulty.
pressure is lower than -0.01MPa,the compressor
and keep it not to decrease than -0.01MPa.If the
Measure the low pressure by the pressure gauge