Midea MCCDH30A-TA3SL, Technical & Service Manual

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Air-cooled modular chiller unit
1
3) T4, T3B and T3A: when the temperature sensor is detected to suffer open circuit or short circuit, fault alarm will occur.
●
When the main unit suffer fault of temperature sensor: the main unit and subordinate units will be shut down.
●
When the subordinate unit suffer fault of temperature sensor: the unit will be shut down, but other subordinate units will
not be affected.
5 Shell and tube low-temperature ant-freeze sensor (Fault code Eb).
6
Unit outlet water temperature sensor (Fault code E4)
Under refrigeration mode and heating mode, conduct adjustment according to the magnitude of unit outlet water
temperature.
Adjustment range of constant speed capability: ON and OFF.
7 Inlet water temperature sensor (Fault code EF).
8
Total outlet water temperature sensor (Fault code E3).
Only the main unit is valid, and the subordinate units are invalid.
Under refrigerating mode and heating mode, conduct adjustment according to the magnitude of total outlet water
temperature. Adjustment range: Load, stabilize, unload, Emergency Stop.
9
1.Dial the code S7 in the main control board to the
“
ON
”
position and enter to the remote control mode (The wired
controller is invalid).
2.First, the ON/OFF port is closed, the second, if this port is closed, the unit enters the heating mode, else, the unit enters
the cooling mode. Remote mode control port(ON/OFF signal, effect on NO.0 unit)
10
1) Dial the code S7 in the main control board to the “ON” position and enter to the remote control mode (The wired
controller is invalid).
Remote control port(ON/OFF signal,effect on NO.0 unit).
11 Electronic expansion valve of the system B
12
Numerical code tube.
1) In case of stand-by, the address of the module is displayed.
2) In case of normal operation, 10 is displayed (10 is followed by dot).
3) In case of fault or protection, fault code or protection code is displayed.
13
Electronic expansion valve in system A.
Electronic expansion valve is used to control refrigerant flow under different operating modes and different loads.
14
Spot check. The operating status of outdoor system can be observed through spot check, and specific display contents are
as shown in the following figure:
Normal display
Operating mode Operating capability of the compressor B Number of online units Outdoor ambient temp. Temp. of the condenser A
T61 frost-proof temp Unit outlet water temp Unit outlet-water tempe Temp. of the condenser B
EXV opening A EXV opening B Operating current of system A Operating current of system B
The last failure
●
Display contents of
“
operating mode
”
: 1. cooling; 2. heating; 4. pump; 8. Stand-by.
●
Display contents of
“
number of online units
”
: the main unit can display the number of online units, and the subordinate
unit displays 0.
15
High-pressure protection of the system A and discharge temperature switch protection (Protection code P0).
High-pressure protection of the system B and discharge temperature switch protection (Protection code P2).
Low-pressure protection of the system A (Protection code P1).
Low-pressure protection of the system B (Protection code P3).
Constant speed compressor: connection of discharge temperature switch and high-pressure switch of the system in series.
16 Power phase detection(Fault code E8).
17
Water flow detection (Fault code of the main unit E9) is only valid for the main unit but invalid for subordinate units.
1) Main unit: if abnormal water flow occurs for the first and second time, the main unit board will display fault code E9.