Mitsubishi Electric M Serie Manuel D'installation page 32

14. Test run
14.1. Before test run
After completing installation and the wiring and pip-
ing of the indoor and outdoor units, check for re-
frigerant leakage, looseness in the power supply or
control wiring, wrong polarity, and no disconnection
of one phase in the supply. Use a 500-volt megohm-
meter to check that the resistance between the pow-
er supply terminals and ground is at least 1.0 MΩ.
Do not carry out this test on the control wiring (low
voltage circuit) terminals.
WARNING
Do not use the air conditioner if the insulation
resistance is less than 1.0 MΩ.
After installation or after the power source to the unit
has been cut for an extended period, the insulation
resistance will drop below 1 MΩ due to refrigerant
accumulating in the compressor. This is not a mal-
function. Perform the following procedures.
1. Remove the wires from the compressor and
measure the insulation resistance of the com-
pressor.
2. If the insulation resistance is below 1 MΩ, the
compressor is faulty or the resistance dropped
due the accumulation of refrigerant in the com-
pressor.
3. After connecting the wires to the compressor,
the compressor will start to warm up after pow-
14.2. Test run
Refer to the installation manual that comes with each remote controller for details.
14.3. Self-check
Refer to the installation manual that comes with each remote controller for details.
Specifications are subject to change without notice.
SVZ-KP12, 18, 24, 30, 36NA
er is supplied. After supplying power for the
times indicated below, measure the insulation
resistance again.
• The insulation resistance drops due to accu-
mulation of refrigerant in the compressor. The
resistance will rise above 1 MΩ after the
compressor is warmed up for two to three
hours.
(The time necessary to warm up the com-
pressor varies according to atmospheric con-
ditions and refrigerant accumulation.)
• To operate the compressor with refrigerant
accumulated in the compressor, the com-
pressor must be warmed up at least 12 hours
to prevent breakdown.
4. If the insulation resistance rises above 1 MΩ,
the compressor is not faulty.
CAUTION
• The compressor will not operate unless the
power supply phase connection is correct.
• Turn on the power at least 12 hours before
starting operation.
– Starting operation immediately after turning
on the main power switch can result in se-
vere damage to internal parts. Keep the
power switch turned on during the operation-
al season.
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