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Notions on refrigerant piping connection
6 NOTIONS ON REFRIGERANT PIPING CONNECTION
The length of the refrigerant pipes aects performance and energy eciency of the unit. The nominal eciency is tested
on units whose pipes are 5 meters long.
For tropical areas, the maximum length of the coolant pipe must not exceed 10 metres. Refer to the following table for
specifications on maximum pipe length and height dierence
27M 35M 53M 70M
Max equivalent length m 25 25 30 50
Max. height dierence Outdoor unit / Indoor unit m ±10 ±10 ±20 ±25
6.1 Refrigerant piping connections
6.1.1 Cut the pipes
When preparing the coolant pipes, take great care to
cut and flare them correctly. This will ensure ecient
operation and reduce the need for further maintenance.
For units with R32 refrigerant, the pipe connection
points must be outside the room.
1 Measure the distance between the indoor and
outdoor unit.
2 Using a pipe cutter, cut the pipe to a measurement
slightly longer than the measured distance.
3 Check that the pipe is cut at an exact 90° angle. Refer
to the examples of incorrect cutting contained in “Fig.
14”.
90°
Oblique Irregular Corrugated
Fig. 14
m
CAUTION
Do not damage, tighten or deform the pipe
during cutting. This would greatly reduce the
heating eciency of the unit.
6.1.2 Eliminate smudges
Deburring can make the refrigerant piping connection
seal less eective. For this reason, they must be
eliminated completely.
1 Keep the pipe tilted downwards to prevent debris
residue from falling into the pipe.
2 Using a reamer or similar tool, remove all burrs from
the cut section of the pipe.
Pipe
Reamer
Tilt downward
Fig. 15
m
CAUTION
Do not damage, tighten or deform the pipe
during cutting. This would greatly reduce the
heating eciency of the unit.