Mitsubishi Electric PUHZ-HRP-HA2, Installation Manual

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10
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 confi rm the unit works without
any problems, before starting the following settings.
►
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
mode.
[Display ]
MAINTENANCE
►
How to start the initial learning
2 Press 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.
TEST
A
CLOCK
7. Test run
7.1. Before test run
►
After completing installation and the wiring and piping of the indoor and
outdoor units, check for refrigerant leakage, looseness in the power sup-
ply or control wiring, wrong polarity, and no disconnection of one phase in
the supply.
►
Use a 500-volt megohmmeter to check that the resistance between the
power supply terminals and ground is at least 1.0M " .
►
Do not carry out this test on the control wiring (low voltage circuit) termi-
nals.
Warning:
Do not use the air conditioner if the insulation resistance is less than 1.0M " .
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 M
"
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 M
"
, the compressor is faulty or the resis-
tance 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 M
" after the compressor is warmed
up for four hours.
(The time necessary to warm up the compressor varies according to atmo-
spheric 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 M " , the compressor is not faulty.
Caution:
• The compressor will not operate unless the power supply phase connec-
tion 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
operational season.
►
The followings must be checked as well.
• The outdoor unit is not faulty. LED1 and LED2 on the control board of the out-
door unit fl ash 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.
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.
• 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.
Note : Occasionally, vapor that is made by the defrost operation may seem
as if smoke come up from the outdoor unit.
7.2. Unit replacement operation
►
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.
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
fl ow from the indoor unit during the replacement operation.
* During the replacement operation, TEST RUN is displayed on the remote
controller and LED1 and LED2 on the control board of the outdoor unit fl ash
together.
3
The duration of the replacement operation is determined by the length of the
piping. 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.
(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 Replacement Operation Time
0 to 20 meters 30 minutes or more
21 to 30 meters 45 minutes or more
31 to 50 meters 60 minutes or more
(2)Allow the replacement operation to automatically stop after 2 hours (opera-
tion 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 con-
ditioning operation is possible with SW8-2 set to ON. However, to repeat
the replacement operation, SW8-2 fi rst 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.
8.Initial settings for refrigerant leakage detection function
[Display ]
Remote control button positions
D
A C B
Operation mode Compressor information Outdoor unit information Indoor unit information
Confirm
Activate/cancel maintenance mode
GAS LEAK
JUDGE
GAS LEAK
TEST START
Refrigerant leakage
detection judgment
Refrigerant
leakage detection
(initial teaching)
A
Fig. 8-1
Fig. 8-2