Mitsubishi Electric Hydrobox EHSD-VM2D - Service and Maintenance; Error Codes

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Service and Maintenance
en
The indoor hydrobox must be serviced once a year by a qualied individual. Ser-
vicing and maintenance of the outdoor unit should only be done by a Mitsubishi
Electric trained technician with relevant qualications and experience. Any electri-
cal work should be done by a tradesperson with the appropriate electrical quali-
cations. Any maintenance or ‘DIY’ xes done by a non-accredited person could
invalidate the Warranty and/or result in damage to the hydrobox and injury to the
person.
Error Codes
Code Error Action
L3 Circulation water temperature overheat protection
Flow rate may be reduced. Check for;
• Water leakage
• Strainer blockage
• Water circulation pump function (Error code may display during lling
of primary circuit, complete lling and reset error code.)
L4 DHW tank water temperature overheat protection Check the immersion heater and it’s contactor.
L5
Indoor unit temperature thermistor (THW1, THW2, 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 may have become dislodged.
L9
Low primary circuit ow rate detected by ow sensor or ow switch (ow switches 1, 2, 3)
See Action for L3. If the ow sensor or ow switch itself does not work,
replace it.
Caution: The pump valves may be hot, please take care.
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 ow 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. (primary / sanitary)
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 ow rate range for outdoor heat pump unit
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 wireless 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 receiver and wireless remote controller
Check wireless remote controller’s battery is not at.
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 outdoor unit
Check that the outdoor unit has not been turned off.
Check connection cable for damage or loose connections.
Refer to outdoor unit service manual.
E9 Outdoor unit receives no signal from indoor unit.
Check both units are switched on. Check connection cable for damage or
loose connections. Refer to outdoor unit service manual.
U*, F* Outdoor unit failure Refer to outdoor unit service manual.
A* M-NET communication error Refer to outdoor unit service manual.
Note: To cancel error codes please switch system off (Press button F4(RESET) on main remote controller).