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Design & installation Guide For McQuay MDS Multi System
5.2 Trial Run
■ Precautions
● Power up the system 12 hours while you run it for the first time so that the shaft can be preheated in
advance;
● After the main power supply is switched off, please don ’t start the second trial run until the system is
powered for 2.5 hours;
● If the heater is not heated, to protect the compressor, don't start the system until it is powered for 2 hours.
◆ Check the power supply between the outdoor units and the distribution unit (it is recommended you
use a 3-phase detector).
◆ Check the indoor units.
● Check the power cable and the signal cable of each indoor unit are properly connected (the signal cable
is marked with A and B);
● If the power cable is mixed with the signal cable, the circuit board might go faulty.
● Although the signal cable is not marked in color, please note the color, because the signal cable features
polarity;
● Check if the addresses are correctly set for the indoor units;
● Address switches begin with 0;
● Each indoor unit must be configured with a different address.