Mitsubishi Electric EHWT17D-MHEDW, Руководство по установке

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Service and Maintenance
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Error Codes (FTC)
Code Error Action
L3
Circulation water temperature overheat protec-
tion
Flow rate may be reduced. Check for;
• Water leakage
• Strainer blockage
• Water circulation pump function (Error code may display during filling of
primary circuit, complete filling and reset error code.)
L4
DHW tank water temperature overheat protec-
tion
Check the immersion heater and it’s contactor.
L5
FTC temperature thermistor (THW1, THW2,
THW5A, THW5B, THW6, THW7, THW8, THW9)
failure
Check resistance across the thermistor.
L6 Circulation water freeze protection See Action for L3.
L8 Heating operation error Check and re-attach any thermistors that have become dislodged.
L9
Low primary circuit flow rate detected by flow
sensor or flow switch (flow switches 1, 2, 3)
See Action for L3. If the flow sensor or flow switch itself does not work, re -
place it.
Caution: The pump valves may be hot, please take care.
LA Pressure sensor failure
1. Connector/terminal wire has be-
come detached or loose wiring.
2. Pressure sensor fault
3. FTC board failure
1. Check pressure sensor cable for
damage or loose connections.
2. Electrically test to determine fault.
3. Replace board.
LC
Boiler circulation water temperature overheat
protection
Check if the setting temperature of the Boiler for heating exceeds the re-
striction. (See the manual of the thermistors "PAC-TH012HT-E")
Flow rate of the heating circuit from the boiler may be reduced.
Check for
• water leakage,
• strainer blockage
• water circulation pump function.
LD Boiler temperature thermistor (THWB1) failure Check resistance across the thermistor.
LE Boiler operation error See Action for L8. Check the status of the boiler.
LF Flow sensor failure Check flow sensor cable for damage or loose connections.
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)
• Check for disconnection of DHW tank water temp. thermistor (THW5B).
• Flow rate of the sanitary circuit may be reduced.
• Check for water circulation pump function.
LL
Setting errors of DIP switches on FTC control
board
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).
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).
LP Out of water flow rate range
Check the installation Table 4.3.1
Check remote controller settings (Service menu / heat pump flow rate
range)
See Action for L3.
J0
Communication failure between FTC and wire-
less receiver
Check connection cable for damage or loose connections.
P1 Thermistor (Room temp.) (TH1) failure Check resistance across the thermistor.
P2 Thermistor (Ref. liquid temp.) (TH2) failure Check resistance across the thermistor.
P6 Anti-freeze protection of plate heat exchanger
See Action for L3.
Check for correct amount of refrigerant.
J1 - J8 Communication failure between wireless receiv-
er and wireless remote controller
Check wireless remote controller’s battery is not flat.
Check the pairing between wireless receiver to wireless remote controller.
Test the wireless communication. (See the manual of wireless system)
E0 - E5 Communication failure between main remote
controller and FTC
Check connection cable for damage or loose connections.
E6 - EF Communication failure between FTC and C.B.
Check connection cable for damage or loose connections.
Refer to service handbook.
E9 C.B. receives no signal from FTC.
Check connection cable for damage or loose connections. Refer to service
handbook.
U*, F* Refrigerant or ambient loop failure Refer to Error Codes (C.B.) or service handbook.
Note: To cancel error codes please switch system off (Press button F4(RESET) on main remote controller, for 3 seconds).
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