Refrigerant Piping Connection - Carrier 18K Installationshandbuch

Refrigerant Piping Connection

When connecting refrigerant piping, do not let substances or gases other than the specified refrigerant enter the
unit. The presence of other gases or substances will lower the unit's capacity, and can cause abnormally high
pressure in the refrigeration cycle. This can cause explosion and injury.
Note on Pipe Length
Ensure that the length of the refrigerant pipe, the number of bends, and the drop height between the indoor and
outdoor units meets the requirements shown in the following table:
The Maximum Length And Drop Height Based on Models. (Unit: m/ft.)
Type of model
North America, Australia and
the eu frequency conversion
Split Type
Other Split Type
CAUTION
Oil traps
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 6m(20ft) of
vertical suction line riser
(<36000Btu/h unit).
An oil trap should be installed every 10m(32.8ft) of
vertical suction line riser
(≥36000Btu/h unit).
Capacity (Btu/h)
<15K
≥15K - <24K
≥24K - <36K
≥36K - ≤60K
12K
18K-24K
30K-36K
42K-60K
Indoor unit/
Outdoor unit
Length of piping Maximum drop height
25/82
30/98.4
50/164
65/213
15/49
25/82
30/98.4
50/164
Gas piping
Oil trap
Liquid piping
10/32.8
20/65.6
25/82
30/98.4
8/26
15/49
20/65.6
30/98.4
Indoor unit/
Outdoor unit
6m/20ft
(<36000Btu/h unit)
10m/32.8ft
(≥36000Btu/h unit)
6m/20ft
(<36000Btu/h unit)
10m/32.8ft
(≥36000Btu/h unit)
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