Midea M-thermal Mono Series, Installation And Owner'S Manual

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1. Check that all shut off valves of the water circuit are
completely open.
2. Check if the water filter needs cleaning.
3. Refer to "9.5 Filling water"
4. Make sure there is no air in the system (purge air).
5. Check the water pressure. The water pressure must be >1
bar(water is cold).
6. Check that the pump speed setting is on the highest speed.
7. Make sure that the expansion vessel is not broken.
8. Check that the resistance in the water circuit is not too high
for the pump. (refer to "10.5 The circulation pump" ).
|Tw_out - Tw_in| value too
big protection
CAUTION
In winter, if the unit has E0 and Hb failure and the unit is not repaired in time, the water pump and pipeline system
may be damaged by freezing, so E0 and Hb failure must be repaired in time.
ERROR
CODE
MALFUNCTION
OR PROTECTION
FAILURE CAUSE
AND CORRECTIVE ACTION
1.wire doesn’t connect between hyraulic module parallel.
connect the wire.
2.Communication wire sequence is not right. Reconnect the
wire in the right sequence.
3. Whether there is a high magnetic field or high power
interfere, such as lifts, large power transformers, etc.. To add a
barrier to protect the unit or to move the unit to the other place.
Communication fault between
hydraulic module parallel
1.wire doesn’t connect between hydraulic module and
temperature. connect the wire.
2.Communication wire sequence is not right. Reconnect the
wire in the right sequence.
3. Whether there is a high magnetic field or high power
interfere, such as lifts, large power transformers, etc.. To add a
barrier to protect the unit or to move the unit to the other place.
Communication fault between
hydraulic module and
temperature
Tw_out - Tw_in unusual
protection
Anti-freeze mode
1.Check the resistance of the two sensor
2.Check the two sensors locations
3.The water inlet/outlet sensor wire connector is loosen.
Reconnect it.
4.The water inlet/outlet
（
TW_in /TW_out
）
sensor is broken,
Change a new sensor.
5. Four-way valve is blocked. Restart the unit again to let the
valve change the direction.
6.Four-way valve is broken, change a new valve.
Unit will return to the normal operation automatically.