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Midea R410A Direct Heating Commercial Heat Pump 50Hz Technical Manual MCAC-HTSM-201506
43
When power supply wire of the wired controller is less than 20m, wiring can be applied as
the location shown as imaginary lines, when it it exeeds 20m, the power adapter is
necessery.
Pay attention to the power phase sequence, if wrong connection of the phase sequence,
the compressor will not operate, and digital screen of the water heater electrical control
board will display error code. Change the phase sequence, and powering again until the
digital screen does not display error and compressor starts normally.
The water flow switch, water pump, ON/OFF singal and E-heater are only connected with
the host unit, which are not 220V control signal. So do not directly drive loading.
When the host unit has any one error of E1, E2 or E8, all the water heaters stop operation.
When the main unit has E4 error, the host unit and wired controller alarm the error, the slave
units do not display error, then all the unit can not normally heat water, and go into backup
mode.
When the host unit has other errors (except E1, E2, E8), then only stop the host unit, other
units will not be affected. When the slave unit has error, only stop the operation of the error
unit, other units will not be affected.
When the main or slave unit has protecton, only stop that unit, other units will not be
affected.