Mitsubishi Heavy Industries FDCW100VNX-A, Technical Manual

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Service
'19 • HM-T-340
228 - Failed defrosting
If the phenomenon persists,
If the phenomenon persists,
Replace the indoor unit relay board AA23.
Replace the pump.
Bleed the air in the water line.
Clean - up the strainer.
Replace the valve(s).
Replace the indoor relay board AA23.
Is air - bleed done properly?
Is the operation signal of the
valves outputted correctly?
Is the valve(s)
functioning properly?
Is there clogging on the strainer
on the water line?
Is the circulation pump setting
(5.11.1.2) done properly?
Is the min supply cooling setting
(1.9.3.2) too low?
Set the value higher so as not
to affect the room comfort.
Set the appropriate value
to obtain enough water flow.
Is the operation signal
of the pump outputted correctly?
Replace the sensor.
Open it.
Are the characteristics of the condenser
out sensor (BT12) OK?
Is the service valve on the
water line open?
YES
YES
YES
YES
NO
NO
YES
YES
NO
NO
YES
YES
YES
NO
NO
NO
NO
Is the water flow rate bigger than
minimum flow rate
NO
YES
NO
YES
NO
YES
NO
Attach wind protection on
outdoor unit.
Fix it and recharge
refrigerant.
Charge correct amount of
refrigerant
YES
Is the outdoor unit;
1
）
installed where wind blows
into directly
and
2
）
not equipped with wind
protection?
Is the refrigerant charged
correctly according to piping
length?
Does the refrigerant leak from
somewhere else?
Troubleshooting guide