Test Run; Before Test Run; Using Sw4 In Outdoor Unit; Using Remote Controller - Mitsubishi Electric Mr. Slim PUHZ-RP.HA Installationshandbuch

7. Test run

7.1. Before test run

s After completing installation and the wiring and piping of the indoor and outdoor
units, check for refrigerant leakage, looseness in the power supply or control
wiring, wrong polarity, and no disconnection of one phase in the supply.
s Use a 500-volt megohmmeter to check that the resistance between the power
supply terminals and ground is at least 1.0MΩ Ω Ω Ω Ω .
s 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 1.0MΩ Ω Ω Ω Ω .
Insulation resistance
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 accumulat-
ing in the compressor. This is not a malfunction. Perform the following procedures.
1. Remove the wires from the compressor and measure the insulation resistance of
the compressor.
2. If the insulation resistance is below 1 MΩ, the compressor is faulty or the resist-
ance dropped due the accumulation of refrigerant in the compressor.
3. After connecting the wires to the compressor, the compressor will start to warm
up after power is supplied. After supplying power for the times indicated below,
measure the insulation resistance again.
• The insulation resistance drops due to accumulation of refrigerant in the com-
pressor. 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 compressor varies according to atmos-
pheric conditions and refrigerant accumulation.)
7.2. Unit replacement operation
s When reusing existing pipes that carried R22 refrigerant, replacement op-
eration must be performed before performing a test run.
• If new pipes are used, these procedures are not necessary.
• If existing pipes that carried R22 refrigerant are used for RP35-71 models, these
procedures are not necessary. (The replacement operation cannot be performed.)
Replacement operation procedures
1 Supply power.
2 Set DIP switch SW8-2 on the control board of the outdoor unit to ON to start
replacement operation.
* The replacement operation is performed using the cooling system. Cool air will
flow from the indoor unit during the replacement operation.
7.3. Test run

7.3.1. Using SW4 in outdoor unit

1) PUH Type, PUHZ Type
SW4-1 ON
Cooling operation
SW4-2 OFF
SW4-1 ON
Heating operation
SW4-2 ON
2) PU Type
SW4-1 ON
Cooling operation
SW4-2 ON or OFF
* After performing the test run, set SW4-1 to OFF.
• To operate the compressor with refrigerant accumulated in the compressor,
the compressor 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
severe damage to internal parts. Keep the power switch turned on during the op-
erational season.
s The followings must be checked as well.
• The outdoor unit is not faulty. LED1 and LED2 on the control board of the outdoor
unit flash when the outdoor unit is faulty.
• Both the gas and liquid stop valves are completely open.
• A protective sheet covers the surface of the DIP switch panel on the control board of
the outdoor unit. Remove the protective sheet to operate the DIP switches easily.
• Make sure that the all of the SW5 DIP switches for function changes on the control
board of the outdoor unit are set to OFF. If all of the SW5 switches are not set to
OFF, record the settings and then set all of the switches to OFF. Begin recovering
the refrigerant. After moving the unit to a new location and completing the test run,
set the SW5 switches to the previously recorded settings.
* During the replacement operation,
and LED1 and LED2 on the control board of the outdoor unit flash together.
3 Replacement operation requires at least two hours to complete.
* After setting switch SW8-2 to ON, the unit automatically stops after two hours.
* Replacement operation can be performed repeatedly by setting switch SW8-2
from OFF to ON. Wait at least two hours before starting replacement operation.
(If operation is started in less than two hours, the existing pipes will not be
cleaned and the unit may be damaged.)
4 Set switch SW8-2 to OFF. (Replacement operation is complete.)
* If the indoor temperature is less than 15°C, the compressor will operate inter-
mittently but the unit is not faulty.
• After power is supplied, a small clicking noise may be heard from the inside of the outdoor
unit. The electronic expansion valve is opening and closing. The unit is not faulty.
• A few seconds after the compressor starts, a clanging noise may be heard from the
inside of the outdoor unit. The noise is coming from the check valve due to the small
difference in pressure in the pipes. The unit is not faulty.
The test run operation mode cannot be changed by DIP switch SW4-2 during
the test run. (To change the test run operation mode during the test run, stop
the test run by DIP switch SW4-1. After changing the test run operation mode,
resume the test run by switch SW4-1.)

7.3.2. Using remote controller

Refer to the indoor unit installation manual.
TEST RUN is displayed on the remote controller
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