Checking The Pump Inv Board For Damage (During Pump Operation); Checking The Installation Conditions; Solutions For The Main Breaker Trip - Mitsubishi Electric PURY-M200YNW-A1 Service Handbook

[8-10 Troubleshooting Inverter Problems ]
8-10-14

Checking the Pump INV Board for Damage (During pump operation)

Items to be checked
Operate the outdoor unit and the
HBC.
Wait until the inverter output frequen-
cy is stabilized, and then check the
inverter output voltage.
8-10-15

Checking the Installation Conditions

Items to be checked
(1) Check refrigerant charge.
(2) Check outdoor unit branch in-
stallation.
8-10-16

Solutions for the Main Breaker Trip

Measure the secondary voltage of the main power breaker before checking because the main power breaker may have been
broken.
Items to be checked
[1] Check the breaker capacity.
[2] Perform Meg check between the
terminals on the power terminal
block TB1.
[3] Turn on the power again and
check again.
[4] Turn on the outdoor unit and check
that it operates normally.
BS_08_L
Phenomena
1) Overcurrent-related error occurs im-
mediately after the startup of the
pump or during operation of the
pump.
Check code: 4255, 4256
Detail code: 101, 102, 103, 106, 107
2) After the inverter output voltage is
stabilized, line voltage imbalance of
at least 5% or 5 V occurs.
Phenomena
Overcharge of refrigerant
The branch approach <500 mm.
Is the branch angle < ±15° to horizontal? Make branch angle < ±15°
Phenomena
Use of a non-specified break-
er
Zero to several ohm, or Meg
failure
1) Main power breaker trip
2) No remote control display
1) Operates normally without
tripping the main breaker.
2) Main power breaker trip
Remedy
a. Check that the results of the
check items in [8-10-11 Checking
the Pump Motor for Ground Fault
and Coil Resistance Problems]
through [8-10-13 Checking the
Pump INV Board for Damage
(Without load)] are OK.
→If the error persists after sever-
al compressor restarts, go to "b."
b. After the startup of the compres-
sor, check the high and low pres-
sures for a proper differential
pressure. (Water pressure)
If a proper differential pressure
does not exist, replace the pump.
(The pump may be locked.)
If line voltage imbalance exists:
<INV/S20>
Replace the INV board.
Remedy
Return to correct refrigerant
charge.
Make branch approach >500mm
Remedy
Replace it with a specified breaker.
Check each part and wiring.
Refer to the following page(s). [8-10-18
Simple Check on Inverter Circuit Compo-
nents]
IGBT module
Rush current protection resistor
Electromagnetic relay
DC reactor
a) The wiring may have been short-circuit-
ed. Search for the wire that short-circuit-
ed, and repair it.
b) If item a) above is not the cause of the
problem, refer to [8-10-2 Checking the
Inverter Board Error Detection Circuit] -
[8-10-10 Checking the Fan Board for
Damage with Load]
49
chapter 8 -