Gree LSQWRF60VM/NhA-M - Page 69

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Test Operation, Troubleshooting and Maintenance
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Check for a single unit
(1) Commission one single unit rst and stop all others.
(2) Do the compressor, fans and the 4-way valve run normally without any unusual noise?
(3) Is the voltage phase difference lower than ±2%?
(4) Voltage phase difference =(phase difference between the max and average voltage)/(average
voltage)×100%.
(5) Start up this single unit.
(6) Do its compressor, fans and the 4-way valve run normally without any unusual noise?
(7) Check other units one by one in the same way.
◆
Check for the water ow of a single unit
In order to prevent the water temperature changing too quickly, it is suggested to open all terminal
units in commissioning, and observe and record the pressure drop of the manometers at the outlet
and inlet pipes. Also, adjust the ow control valves or shut-off valves to make the ow meet application
requirements.
When the environmental temperature is available, let the unit perform cooling (>15°C). When the unit
has run stably for 10 minutes, the normal difference of the entering and leaving water should be 4-6°C.
(1) If the temperature difference is larger than 4-6°C, raise it by reducing the water ow of other units.
(2) If the temperature difference is smaller than 4-6°C, ignore it in the event that the difference of other
units is suitable, and reduce the water ow of this unit in the event that the difference of other units
is also unsuitable.
(3) Check for the water ow of other units one by one in the same way.
◆
Check for operation of the whole unit
(1) Check the difference of the entering and leaving water temperature of each unit when the whole
unit has been in operation. If temperature adjustment fails, reconsider the capacity of the selected
water pump.
(2) Start up the whole unit under the full load. When the whole unit has run stably for one hour, check if
the water temperature and the air conditioning effect meet the user’s requirements.
(3) Observe and record the entering and leaving water temperature, condensing and evaporating
pressure. Then, stop the unit and check the setpoint of each parameter on the control panel. After
that, complete the commissioning date sheet.
(4) When the unit comes to the protection state, diagnose it and and seek solutions.