Mitsubishi Electric EHPT20X-VM2HA, Руководство по обслуживанию

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47
Error code Title and display conditions Possible Cause Diagnosis and action
L9
Low primary circuit flow rate detected by
flow switch
<DHW/Heating/LP/FS>
Error code displayed when flow switch
detects low flow rate for 10 seconds.
Exception
For 3 mins after water circulation pump1 is
switched on.
1
Insufficient system head
1
Refer to table in section 10-6. to determine
if system pump meets requirements.
If more head required either add an pump
of the same size or replace existing pump
with capacity model.
See 11. DISASSEMBLY PROCEDURE for
how to replace pump.
2
Reduced flow in primary water circuit
Due to 1 or more of the following;
Faulty pump, insufficient air purge, blocked
strainer, leak in water circuit.
2
Check circulation pump (See 10-6. for how
to check).
Open purge valve to remove trapped air.
Check the strainer for blockages.
Check the primary water circuit for leaks.
Check that the flow amount is within the
recommended range.
3 Valve operation fault 3
Check valves on primary water circuit are
installed level.
4
2-way valve (field supply) actuator
fault
4
Electrically test to determine fault.
5
Connector/terminal wire has become
detached or loose wiring.
5 Visually check the CNF connector and IN
terminal and reattach if necessary.
6
Flow switch fault
6 Electrically test to determine fault.
See 10-6. for how to check.
7 FTC3 board failure
Incorrect setting of SW2-2.
7 Replace board.
8
Incorrect setting of the SW2-2
8
Check the SW2-2 setting.
E0/E4 Main controller communication failure
(Reception error)
Error code E0 is displayed if main controller
does not receive any signal from the indoor
unit for ref. address "0" for 3 mins.
Error code E4 is displayed if indoor unit
does not receive any data from the main
controller for 3 mins or indoor unit does not
receive any signal from the main controller
for mins.
1
Contact failure with transmission cable
1
Check connection cable for damage or loose
connections at the FTC3 and main controller
terminals.
2
Wiring procedure not observed.
(Cable length/cable diameter/number of
indoor units/number of main controllers)
2
Check main controller and FTC3 common
wiring max cable length 500 m.
Only use core cable.
Only connect 1 main controller to 1 FTC3
indoor unit board.
3 Fault on the indoor unit FTC3 board section
controlling Ref. address "0"
3
to
5
If the problem is not solved by the above
measures then:
Turn the power to the indoor unit OFF and
then ON.
Power to both the indoor unit and outdoor
units should be switched OFF then ON. (This
may require switching 1 or 2 breakers de
-
pending if the unit is powered independently
from the outdoor unit).
If the E4 code is still displayed the FTC3
and/or the main controller circuit board
should be replaced.
4
Fault with the main controller circuit board
5
Electrical noise causes interference with
transmission/reception of data for main
controller.
E3/E5 Main controller communication failure
(Transmission error)
Error code E3 is displayed if the main
controller an not find an empty transmission
path and thus fails to transmit for 6 secs
or the data received bythe main controller
is different to what was sent (by the main
controller) 30 consecutive times.
Error code E5 is displayed if the FTC3 can
not find an empty transmission path for 3
mins and thus cannot transmit or the data
sent by the FTC3 is different to what was
expected 30 consecutive times.
1 or more main controllers have been
connected to the FTC3. 1 Only connect 1 main controller to 1 FTC3
indoor unit board.
2
Fault with main controller transmission/
receiving circuit board
2
to
4
Turn the power to the indoor unit OFF and
then ON.
Power to both the indoor unit and outdoor
units should be switched OFF then ON.
(This may require switching 1 or 2 breakers
depending if the unit is powered independ
-
ently from the outdoor unit).
If the E3/E5 code is still displayed the FTC3
and/or the main controller circuit board
should be replaced.
3
Fault with the main controller circuit board
4
Electrical noise causes interference with
transmission/reception of data for main
controller.
E6 Indoor/outdoor communication failure
(Reception error)
Error code E6 is displayed if after the power
is switched ON to the indoor unit, the FTC3
board does not receive any signal or the
signal receivedis not complete for 6 mins, or
after a period of operation the FTC3 board
does not receive any signal or the signal
received is not complete for 3 mins.
Check the LED display on the outdoor unit
circuit board.
(Connect the A-control service tool, PAC-
SK52ST to test.) Refer to the outdoor unit serv
-
ice manual for explanation of EA-EC codes.
1
Contact failure/short circuit/miswiring
1
Check the connections on the indoor and
outdoor units have not become loose and
that the connecting cable is not damaged.
2
Fault with outdoor unit transmission/
receiving circuit board
2
to
4
Turn the power to the indoor unit OFF and
then ON.
Power to both the indoor unit and outdoor
units should be switched OFF then ON.
(This may require switching 1 or 2 breakers
depending if the unit is powered independ
-
ently from the outdoor unit).
If the E6 code is still displayed the FTC3
and/or the outdoor unit circuit board should
be replaced.
3
Fault with FTC3 transmission/receiving
circuit board
4
Electrical noise causes interference with
FTC3-Outdoor unit transmission cable.