Maintenance - Mitsubishi Electric MR.SLIM SEZ-KD25 Installationshandbuch

9. Test run
• If the unit cannot be operated properly after the above test run has been performed, refer to the following table to remove the cause.
Wired remote controller
PLEASE WAIT
PLEASE WAIT → Error code
Display messages do not appear
even when operation switch is
turned ON (operation lamp does
not light up).
On the wireless remote controller with conditions above, following phenomena takes place.
• No signals from the remote controller are accepted.
• OPE lamp is blinking.
• The buzzer makes a short ping sound.
Note:
Operation is not possible for about 30 seconds after cancellation of function selection. (Correct operation)
For description of each LED (LED1, 2, 3) provided on the indoor controller, refer to the following table.
LED 1 (power for microcomputer)
LED 2 (power for remote controller)
LED 3 (communication between indoor and outdoor units)
9.3. AUTO RESTART FUNCTION
Indoor controller board
This model is equipped with the AUTO RESTART FUNCTION.
When the indoor unit is controlled with the remote controller, the operation mode, set
temperature, and the fan speed are memorized by the indoor controller board. The
auto restart function sets to work the moment the power has restored after power
failure, then, the unit will restart automatically.
Set the AUTO RESTART FUNCTION using the wireless remote controller. (Mode
no.1).

10. Maintenance

10.1. Gas charge
[Fig. 10-1] (P.8)
A Indoor unit
B Union
C Liquid pipe
D Gas pipe
E Stop valve
F Outdoor unit
G Refrigerant gas cylinder operating valve
H Refrigerant gas cylinder for R410A with siphon
I Refrigerant (liquid)
J Electronic scale for refrigerant charging
K Charge hose (for R410A)
L Gauge manifold valve (for R410A)
M Service port
1. Connect gas cylinder to the service port of stop valve (3-way).
2. Execute air purge of the pipe (or hose) coming from refrigerant gas cylinder.
3. Replenish specified amount of refrigerant, while running the air conditioner
for cooling.
Symptom
LED 1, 2 (PCB in outdoor unit)
After LED 1, 2 are lighted, LED 2 is turned
For about 2 minutes
off, then only LED 1 is lighted. (Correct
following power-on
operation)
Only LED 1 is lighted. → LED 1, 2 blink.
After about 2 min-
utes has expired
following power-on
Only LED 1 is lighted. → LED 1, 2 blinks
twice, LED 2 blinks once.
Indicates whether control power is supplied. Make sure that this LED is always lit.
Indicates whether power is supplied to the remote controller. This LED lights only in the case of
the indoor unit which is connected to the outdoor unit refrigerant address "0".
Indicates state of communication between the indoor and outdoor units. Make sure that this LED is
always blinking.
• For about 2 minutes after power-on, operation of the
remote controller is not possible due to system start-up.
(Correct operation)
• Connector for the outdoor unit's protection device is not
connected.
• Reverse or open phase wiring for the outdoor unit's power
terminal block (L1, L2, L3)
• Incorrect wiring between indoor and outdoor units
(incorrect polarity of S1, S2, S3)
• Remote controller wire short
Note:
In case of adding refrigerant, comply with the quantity specified for the refrigerating
cycle.
Caution:
• Do not discharge the refrigerant into the atmosphere.
Take care not to discharge refrigerant into the atmosphere during installa-
tion, reinstallation, or repairs to the refrigerant circuit.
• For additional charging, charge the refrigerant from liquid phase of the gas
cylinder.
If the refrigerant is charged from the gas phase, composition change may
occur in the refrigerant inside the cylinder and the outdoor unit. In this case,
ability of the refrigerating cycle decreases or normal operation can be impos-
sible. However, charging the liquid refrigerant all at once may cause the com-
pressor to be locked. Thus, charge the refrigerant slowly.
To maintain the high pressure of the gas cylinder, warm the gas cylinder with warm
water (under 40°C) during cold season. But never use naked fire or steam.
Cause
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