Test Run; Before Test Run; Initial Settings For Refrigerant Leakage Detection Function - Mitsubishi Electric PUHZ-RP35HA2 Manuel D'installation

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.
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.
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.
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.
* During the replacement operation,
and LED1 and LED2 on the control board of the outdoor unit flash together.
3 The duration of the replacement operation is determined by the length of the pip-
ing. Always perform the replacement operation for longer than the stipulated time.
* Use one of the following methods to complete the replacement operation. When
the replacement operation ends, the unit will automatically stop.
7.3. Test run
7.3.1. Using SW4 in outdoor unit
SW4-1 ON
Cooling operation
SW4-2 OFF
SW4-1 ON
Heating operation
SW4-2 ON
* After performing the test run, set SW4-1 to OFF.
• 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.

8. Initial settings for refrigerant leakage detection function

I Remote control button positions
A C B
D
Operation mode Compressor information Outdoor unit information Indoor unit information
Confirm
Activate/cancel maintenance mode
Fig. 8-1
[Display A] Refrigerant
leakage detection
(initial teaching)
GAS LEAK
TEST START
Fig. 8-2
is displayed on the remote controller
TEST RUN
Refrigerant leakage
detection judgment
GAS LEAK
JUDGE
• 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 four hours.
(The time necessary to warm up the compressor varies according to atmos-
pheric conditions and refrigerant accumulation.)
• 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 following 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.
(1) Set SW8-2 from ON to OFF (when ending a replacement operation of less
than 2 hours).
• Because the replacement operation restarts each time SW8-2 is set from
OFF to ON, always perform the replacement operation for longer than the
stipulated time.
Required replacement operation times
Pipe Length
0 to 20 meters
21 to 30 meters
31 to 50 meters
(2) Allow the replacement operation to automatically stop after 2 hours (operation
stops while SW8-2 is still in the ON position).
• When the replacement operation has ended automatically after 2 hours of
operation, there is no need to set SW8-2 from ON to OFF; normal air condi-
tioning operation is possible with SW8-2 set to ON. However, to repeat the
replacement operation, SW8-2 first has to be set to OFF and then to ON.
* If the indoor temperature is less than 15°C, the compressor will operate inter-
mittently but 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.
This air conditioner (outdoor unit) can detect refrigerant leakage which may happen
during a long period of use. In order to enable the leakage detection, the following
settings are required to let the unit memorize the initial conditions (initial learning).
Caution:
Make sure to perform the "7.Test run" and confirm the unit works without any
problems, before starting the following settings.
s How to select the "Refrigerant Leakage Detection" mode
Detection is possible regardless the unit's operation (ON or OFF).
1 Press
button for more than three seconds to switch to the maintenance
TEST
mode.
[Display A]
MAINTENANCE
s How to start the initial learning
2 Press CLOCK button and select the [GAS LEAK TEST START] (Fig. 8-2)
* The initial learning for the leakage detection is always done once after the new
installation or the data reset.
Replacement Operation Time
30 minutes or more
45 minutes or more
60 minutes or more
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