MULTI VRF-Ⅱ  INDOOR UNIT SERVICE MANUAL    EUROPEAN/LATIN AMETICA (R410A) 
109 
 
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Secure a downward gradient of 1/100 or more for the drain pipe. To accomplish this, mount supporting 
brackets at an interval of 1 - 1.5 m.(take the cassette type unit for example) 
 
 
4.4 Testing of Drain Piping   
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  After piping work is finished, check if drainage flows smoothly. 
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Shown in the figure, Add approximately 1liter of water slowly into the drain pan and check drainage flow 
during COOL running.