EAS Electric Super-Slim Cassette Series Owner's Manual page 88

CAUTION
Oil traps
If the indoor unit is installed higher than the
outdoor unit:
-If oil flows back into the outdoor unit's
compressor, this might cause liquid
compression or deterioration of oil return.
Oil traps in the rising gas piping can prevent
this.
An oil trap should be installed every 10m
(32.8ft) of vertical suction line riser.
(See Fig. 7.3)
Fig. 7.3
The indoor unit is installed higher than the
outdoor unit
CAUTION
If the outdoor unit is installed higher than the
indoor unit:
-It is recommended that vertical suction risers
not be upsized. Proper oil return to the
compressor should be maintained with suction
gas velocity. If velocities drop below7.62m/s
(1500fpm (feet per minute)), oil return will be
decreased. An oil trap should be installed every
6m(20ft) of vertical suction line riser.
(See Fig. 7.4)
Fig. 7.4
The outdoor unit is installed higher than the
indoor unit
V.1
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