Mitsubishi Electric ecodan EHPT20X- VM2HB, Руководство по обслуживанию

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Error code Title and display conditions Possible Cause Diagnosis and action
L8 Heating operation error
* “” is displayed in “Request code: 567” in “Run-
ning information”.
<Heating/FS>
If a), b) and c) occur, L8 is displayed;
a)
No change on THW1 and THW5
(under 1 °C for 0 minutes from unit starts
operation)
b)
No change on THW1
(under 1 °C for 10 minutes from booster heater
starts operation)
c) THW1 - THW < -5 °C
(for 10 minutes continuously)
1. THW1 has become detached from its
holder. 1. Visually inspect location and reattach as
necessary.
. Booster heater fault . Electrically test to determine fault.
See 10-6. for how to check.
. THW1 or THW or THW5 fault .
Check resistance of thermistor against ta
-
ble in section 10-6.
Compare FTC4 detected temperature to
hand held detector.
4 .
FTC4 board failure
4 . Replace board.
Heating operation error
* “a” is displayed in “Request code: 567” in
“Running information”.
1. THW6 has become detached from its
holder. 1. Visually inspect location and reattach as
necessary.
. THW6 or THW7 fault .
Check resistance of thermistor against ta
-
ble in section 10-6.
Compare FTC4 detected temperature to
hand held detector.
.
FTC4 board failure
.
Replace board.
Heating operation error
* “c” is displayed in “Request code: 569” in
“Running information”.
1. THW8 has become detached from its
holder. 1. Visually inspect location and reattach as
necessary.
. THW8 or THW9 fault .
Check resistance of thermistor against ta
-
ble in section 10-6.
Compare FTC4 detected temperature to
hand held detector.
.
FTC4 board failure
. Replace board.
L9
Low primary circuit (Heat source side) flow
rate detected by flow switch
* “1” is displayed in “Request code: 569” in “Run-
ning information”.
<DHW/Heating/LP/FS>
Error code displayed when flow switch detects
low flow rate for 10 seconds.
Exception
For 1 min 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.
.
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.
.
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.
.
Valve operation fault
.
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 CN2F 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.
Incorrect setting of the SW2-2
7.
Check the SW2-2 setting.
8.
FTC4 board failure
8. Replace board.
Low primary circuit (Zone1 side) flow rate
detected by flow switch
* “” is displayed in “Request code: 569” in “Run-
ning information”.
1 .
Insufficient system head
1 . If more head required either add an pump
of the same size or replace existing pump .
.
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.
.
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.
.
Terminal wire has become detached
or loose wiring.
. Visually check the IN terminal and reat-
tach if necessary.
4 .
Flow switch fault
4 . Electrically test to determine fault.
5.
Incorrect setting of the SW3-2
5.
Check the SW3-2 setting.
6.
FTC4 board failure
6. Replace board.
OCH531