Refrigerant Piping Connection - Rinnai Pro Series Installation Manual

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.
The branching pipe must be installed horizontally. An angle of more than 10° may cause
malfunction. Insulate the gas and liquid piping to prevent condensation.
DO NOT install the connecting pipe until both the indoor and outdoor units have been installed.
Pipe length
Ensure the length of the refrigerant pipe, the number of bends, and the drop height between the
indoor and outdoor units meets the requirements shown below.
Maximum length and drop height
Model
7 kW
9 - 18 kW
Oil traps
If oil flows back into the unit's compressor this might cause liquid compression or deterioration of
oil return. Oil traps in the rising gas piping can prevent this. For units less than 10.5 kW, an oil trap
should be installed every 6 m of vertical suction line riser. For units greater than or equal to 10.5 kW,
an oil trap should be installed every 10 m of vertical suction line riser.
18 |
Maximum equivalent pipe length
50 m
75 m
Gas piping
Oil trap
Indoor unit/
Outdoor unit
Maximum vertical separation
25 m
30 m
Indoor unit/
Outdoor unit
6m
(<10.5 unit)
10m
Liquid
(≥10.5 unit)
piping
6m
(<10.5 unit)
10m
(≥10.5 unit)