GCH15010
39
* … 1 : Flow sensor 1
2 : Flow sensor A
3 : Flow sensor B
Error code
Title and display conditions
Possible Cause
Diagnosis and action
L9
* “4” is displayed in “Request code: 569” in “Run-
ning information”.
<Heating>
1.
2.
Valve operation fault
3.
2-way valve (local supply) actuator
fault
4.
Connector wire has become detached
or loose wiring.
4.
Visually check the CN1A connector and
reattach if necessary.
5.
Flow sensor 1 fault
5.
Electrically test to determine fault.
See 10-6. for how to check.
6.
6.
FTC board failure
Replace board.
Low primary circuit (Heat source side) flow
rate detected by flow sensor
Exception
While hot water is not supplied.
Error code displayed when flow sensor detects
low flow rate for 10 seconds.
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.
1.
Check circulation pump (See 10-6. for how
to check).
Open air vent 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 during heating
operation.
Refer to Procedure 5 in “11. DISASSEMBLY
PROCEDURE.”
2.
Check valves on primary water circuit are
installed level.
3.
Electrically test to determine fault
* “
5
” is displayed in “Request code: 569” in “Run-
ning information”.
<DHM/Heating/LP/LS>
1.
2.
Valve operation fault
3.
2-way valve (local supply) actuator
fault
4.
Connector wire has become detached
or loose wiring.
4.
Visually check the CN2B connector and
reattach if necessary.
5.
Flow sensor B fault
5.
Electrically test to determine fault.
See 10-6. for how to check.
6.
6.
FTC board failure
Replace board.
Low primary circuit (Heat source side) flow
rate detected by flow sensor
Error code displayed when flow sensor detects
low flow rate for 10 seconds.
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.
1.
Check circulation pump (See 10-6. for how
to check).
Open air vent 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 during heating
operation.
Refer to Procedure 5 in “11. DISASSEMBLY
PROCEDURE.”
2.
Check valves on primary water circuit are
installed level.
3.
Electrically test to determine fault
LF
Flow sensor failure
"*" is displayed in “Request code : 575” in
“Running information”.
LP
1. Thermal store tank water tempareture
is high (THW5A
≧
70
℃)
1.
Refer to L3/L4.
2. THW4 fault
3. FTC board failure
2.
Check resistance of thermistor against
table in section 10-6.
3.
Replace board.
Check flow sensor cable for damage or loose
connections.
LU
1. Power supply voltage increase
1.
Check the supply voltage.
2. Connector/terminal wire has become
detached or loose wiring
2.
Visually check the terminals and connectors
and reattaches appropriate.
3. Water circulation pump is locked
3.
to 5.
Turn the power to the indoor unit OFF and
then ON.
Power to both the indoor unit and outdoor
unit should be switched OFF then ON.
If the LU code is still displayed the water
circulation pump should be replaced.
4. Water circulation pump reaching the
end of life
5. Water circulation pump fault
6. FTC board failure
6.
Replace board.
DHW supply temperature overheat protection
<HW/HT/FS/OS>
Error code displayed when THW4 detects a temp
≧
70
℃
for 5 concecutive seconds.
Exception
Error code will not be displayed if;
While there is no hot water supply,
For 30 seconds after hot water supply start,
DHW supply max. temp. is set to more than 61
℃
,
For 24 hours after DHW supply max. temp. is
changed from more than 61
℃
to less than 60
℃
.
Water circulation pump failure
"*" is displayed in "Request code:576" in "Running
information".
* … 1: Water circulation pump 1
2: Water circulation pump A
<HW/HT/FS/OS>
Error code displayed when
PWM feedback signal is set to 83
〜
92% for 10
concecutive seconds.
Exception
Water circulation pump is OFF.