Concealed Ducted Air Handler Installation Manual

9
Refrigerant Piping Connection
When connecting refrigerant piping, take care to keep all refrigerant lines clean and clear of debris,
moisture and other contaminants. Doing so will help ensure optimal performance and longer
service life.
Note on Pipe Length
Maximum Length and Drop Height of Refrigerant Piping per Unit Model
The length of refrigerant piping will aect the performance and energy eciency of the unit. Nominal
eciency is tested on units with a pipe length of 16.5ft. In North America, standard pipe length is 25’.
A minimum pipe run of 10 feet is required to minimize vibration & excessive noise. Refer to the table
below for specications on the maximum length and drop height of piping.
Model
Max Length Max Drop Height
Add'l Refrigerant
9k & 12k 82 feet 33 feet 0.16/ foot
18k 99 feet 66 feet 0.16/ foot
24k 164 feet 82 feet 0.32/ foot
Refrigerant Piping
Connection
 Page 22 
Revised 5/14/2020
Oil traps If the indoor unit is installed higher than the outdoor unit:
-If oil ows 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 32.8ft of vertical suction line riser.
CAUTION
The indoor unit is installed higher than the
Indoor unit
Gas piping
Oil trap
Outdoor unit
32.8 ft
32.8 ft
Liquid
piping
outdoor unit