Pipe Temperature; Cooling Mode; Heating Mode; Address Duplicate Definition - Mitsubishi Electric PUHZ-RP250YHA2 Service Manual

Abnormal point and detection method
Error Code

Pipe temperature

<Cooling mode>
Detected as abnormal when the pipe tem-
perature is not in the cooling range 3 min-
utes after compressor start and 6 minutes
after the liquid or condenser/evaporator pipe
is out of cooling range.
Note 1) It takes at least 9 minutes to
detect.
Note 2) Abnormality P8 is not detected in
drying mode.
Cooling range : Indoor pipe temperature
(TH2 or TH5) – room temperature
(TH1)
TH: Lower temperature between liquid pipe
temperature and condenser/
P8
evaporator temperature
(1110)
<Heating mode>
When 10 seconds have passed after the
compressor starts operation and the hot
adjustment mode has finished, the unit is
detected as abnormal when condenser/
evaporator pipe temperature is not in heat-
ing range within 20 minutes.
Note 3) It takes at least 27 minutes to
detect abnormality.
Note 4) It excludes the period of defrosting.
(Detection restarts when defrosting
mode is over)
Heating range : 3
Evaporator temperature(TH5) –
room temperature(TH1))
<M-NET communication error>
Error Code Abnormal point and detection method

Address duplicate definition

This error is displayed when transmission
from the units of same address is detected.
A0
Note) The address and attribute displayed
(6600)
at remote controller indicate the con-
troller that detected abnormality.
Hardware error of transmission
processor
Transmission processor intended to trans-
mit "0", but "1" appeared on transmission
wire.
A2
Note) The address and attribute displayed
(6602)
at remote controller indicate the con-
troller that detected abnormality.
BUS BUSY
1. Overtime error by signal collision damage
Abnormal if transmitting signal is not
possible for 8-10 minutes continuously
because of collision of transmission.
2. Data could not reach transmission wire
for 8-10 minutes continuously because
of noise or etc.
Note) The address and attribute displayed
A3
at remote controller indicate the con-
(6603)
troller that detected abnormality.
-3
(Condenser/
Case
Slight temperature difference
between indoor room
temperature and pipe <liquid
or condenser / evaporator>
temperature thermistor
• Shortage of refrigerant
• Disconnected holder of pipe
<liquid or condenser /
evaporator> thermistor
• Defective refrigerant circuit
Converse connection of
extension pipe (on plural units
connection)
Converse wiring of indoor/
outdoor unit connecting wire
(on plural units connection)
Defective detection of indoor
room temperature and pipe
<condenser / evaporator>
temperature thermistor
Stop valve is not opened
completely.
(Note) "Indoor unit" in the text indicates M-NET board in outdoor unit.
Case
There are 2 or more same
address of controller of out-
door unit, indoor unit, FRESH
MASTER, or LOSSNAY.
Noise has entered into trans-
mission signal and signal was
transformed.
Error is detected if waveform is
transformed when wiring works of
transmission wire of outdoor unit,
indoor unit, FRESH MASTER or
LOSSNAY are done, or polarity is
changed with the power on and
transmission data collide each other.
Defective transmitting receiving
circuit of transmission processor
Transmission data is changed by
the noise on transmission.
Transmission processor could
not transmit signal because short
cycle voltage of noise and the
like have entered into transmis-
sion wire continuously.
Transmission quantity has
increased and transmission of
signal is not possible because
there was wiring mistake of ter-
minal block for transmission wire
(TB3) and terminal block for cen-
tral control (TB7) in outdoor unit.
Transmission is mixed with
others and occupation rate on
transmission wire rose because
of defective repeater (a function
to connector or disconnect trans-
mission of control and central
control system) of outdoor unit,
then abnormality is detected.
35
Judgment and action
~ Check pipe <liquid or condenser / evapo-
rator> temperature with room tempera-
ture display on remote controller and
outdoor controller circuit board.
Pipe <liquid or condenser / evaporator>
temperature display is indicated by set-
ting SW2 of outdoor controller circuit
board as follows.
( Conduct temperature check with outdoor
controller circuit board after connecting
'A-Control Service Tool(PAC-SK52ST)'.
Temperature display of indoor condenser/
Temperature display of indoor liquid pipe
evaporator pipe Indoor 1
Indoor 1
1 2 3 4 5 6 1
ON
OFF
Temperature display of indoor condenser/
Temperature display of indoor liquid pipe
evaporator pipe Indoor 2
Indoor 2
1 2 3 4 5 6
1
ON
OFF
A-Control Service Tool SW2 setting
Check converse connection of extension
pipe or converse wiring of indoor/outdoor
unit connecting wire.
Judgment and action
Search the unit with same address as abnormality
occurred. If the same address is found, turn the
power supply of outdoor unit and indoor unit and
FRESH MASTER or LOSSNAY at the same time
for 2 minutes or more after the address is cor-
rected, and turn the power on again.
Check transmission waveform or noise on trans-
mission wire.
If the work of transmission wire is done with
the power on, turn off the power supply of
outdoor unit and indoor unit and FRESH
MASTER or LOSSNAY at the same time for
2 minutes or more, and turn the power on
again.
Check transmission waveform or noise on
transmission wire.
Check if transmission wire of indoor unit,
FRESH MASTER, LOSSNAY, or remote con-
troller is not connected to terminal block for
central control (TB7) of outdoor unit.
Check if transmission wire of indoor unit,
FRESH MASTER or LOSSNAY is not con-
nected to terminal block for transmission wire
of outdoor unit.
Check if terminal block for transmission wire
(TB3) and terminal block for central control
(TB7) is not connected.
Check transmission waveform or noise on
transmission wire.
)
2 3 4 5 6
ON
OFF
2 3 4 5 6
ON
OFF