45
Error code
Title and display conditions
Possible Cause
Diagnosis and action
L9
Low primary circuit (Zone2 side) flow rate
detected by flow switch
Note: “3” is displayed in “Request code: 569” in
“Running information”.
1.
Insufficient system head
1. If more head required either add an pump
of the same size or replace existing 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.
Checking Component Parts' Function"
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. Terminal wire has become detached
or loose wiring.
3. Visually check the IN7 terminal and reat
-
tach if necessary.
4. Flow switch fault
4.
Electrically test to determine fault.
5. Incorrect setting of the SW3-3
5. Check the SW3-3 setting.
6. FTC board failure
6.
Replace board.
LC
Boiler circulation water temperature overheat
protection
<DHW/Heating/LP/FS/OS>
Error code displayed when THWB1 detects a
temperature ≥80ºC for 10 consecutive seconds
or THWB2 detects a temperature ≥80ºC for 10
consecutive seconds
1. The set temperature for Boiler is too
high.
1. Check if the set temperature for Boiler for
heating exceeds the restriction. (See the
manual for the thermistors "PAC-TH011HT-E")
2.
Flow rate of the heating circuit from the
boiler may be reduced.
2. Check for
• water leakage
• strainer blockage
• water circulation pump function
LD
Boiler temperature thermistor (THWB1, THWB2)
failure
Refer to error codes (P1/P2/L5/LD).
LE
Boiler operation error
<Heating>
Boiler is running and THW6 detects a
temperature <30ºC for consecutive 60 minutes.
1.
THW6 has become detached from its
holder.
1. Visually inspect location and reattach as
necessary.
2.
Incorrect wiring between FTC (OUT10)
and the boiler
2.
See the manual of the thermistors "PAC-
TH011HT-E".
3.
Boiler fuel has run out or the system is
OFF.
3.
Check the status of the boiler.
4.
Boiler failure
4.
Check the status of the boiler.
5. FTC board failure
5.
Replace board.
LF
Flow sensor failure
Disconnection or loose connection of flow
sensor
Check flow sensor cable for damage or loose
connection.
LH
Boiler circulation water freeze protection
Flow rate of the heating circuit from the
boiler may be reduced.
Check for
• water leakage
• strainer blockage
• water circulation pump function
LJ
DHW operation error (type of external plate HEX)
1. DHW tank water temp. thermistor
(THW5)
has become detached from its
holder.
2. Flow rate of the sanitary circuit may be
reduced.
1. Check for disconnection of DHW tank water
temp. thermistor (THW5).
2. Check for water circulation pump function.
LL
Setting errors of DIP switches on FTC control
board
Incorrect setting of DIP switches
1. Boiler operation
1.
For boiler operation, check that DIP SW1-1
is set to ON (With Boiler) and DIP SW2-6 is
set to ON (With Mixing Tank).
2. 2-zone temperature control
2.
For 2-zone temperature control, check DIP
SW2-7 is set to ON (2-zone) and DIP SW2-
6 is set to ON (With Mixing Tank).
3.
Multiple outdoor units control
3. For multiple outdoor units control, check DIP
SW1-3 is set to ON on FTC (slave) that runs
DHW operation .
P1
Indoor unit temperature thermistor (TH1A/TH1B)
failure
Refer to error codes (P1/P2/L5/LD).
P2
Indoor unit temperature thermistor (TH2) failure
Refer to error codes (P1/P2/L5/LD).
P6
Anti-freeze protection of plate heat exchanger
<Cooling>
The error code displayed when Ref. liquid temp.
(TH2) stays at −5ºC or lower for 10 seconds after
compressor operates for 6 minutes.
<Cooling>
1.
Reduced water flow
1., 2.
Check water piping.
• Clogged filter
• Leakage of water
2.
Low temperature
• Low load
• Inlet water is too cold.
3. Defective water pump
3. Check water pump.
4.
Defective outdoor fan control
4.
Check outdoor fan motor.
5. Overcharge of refrigerant
5., 6. Check operating condition of refrigerant circuit.
6. Defective refrigerant circuit (clogs)
7.
Malfunction of linear expansion valve
7.
Check linear expansion valve.
OCH590B
