10
VFH InverterFlex
®
- Outdoor Ductless Mini-Split
Heat Controller
Refrigerant Line Set Installation
Refrigerant Line Set Installation
1. Purchase line sets through a Heat Controller
distributor with consideration of the minimum
and maximum line lengths. (Page 11)
2. Both liquid and suction lines to be insulated.
3. Connections are made via flare nuts.
4. The number of bends and length of refrigerant
lines determine the pressure drop which affects
capacity and efficiency of the system, as well
as oil return. Minimize the length and number of
bends when possible during installation.
5. Minimum line set length must be maintained,
even if the installation does not require it. Extra
length that is unnecessary can be coiled up
near the outdoor unit (Do not to block air inlets/
outlets).
6. Choose a location that places the outdoor
unit as close to the indoor unit as possible to
minimize line set lengths.
7. Use only clean, refrigerant grade tubing suitable
for R-410A.
8. Avoid installing refrigerant lines on wet/rainy
days.
9. Always keep tube ends sealed until the final
connections are to be made.
10. If line sets are being made at the time of
installation, rather than being purchased, be sure
to:
• Remove burrs from cut ends of the tubing
• Use tube benders to prevent kinking.
• Ensure tube cuts are square in relation to the
end of the tube.
• Use the proper diameter tube and flare nut
sizes recommended by the manufacturer.
• Insulate both lines with Amraflex or equivalent
with a wall thickness of at least 3/8".
• Use copper tubing suitable to withstand
pressures for R-410A refrigerant. We
recommend a minimum wall thickness of
0.027 in. (0.7mm).
11. The tube size should always be the same
diameter as the connections provided at the of
the indoor unit.
Note:
On some models, a reducer or an
expander may be shipped with the outdoor
unit in order to adapt the line set connection to
the proper size to mate with the indoor unit’s
connection. Be sure to check for these parts,
should you discover that the outdoor units
service valve sizes differ from the indoor unit’s
connections. If this part is shipped with the
outdoor unit, then it is required to be used.
12.Up sizing/downsizing the refrigerant lines/
connections can result in inadequate oil return to
the compressor or excessive refrigerant return
and will void the warranty.
13.Do not over torque the connections, excessive
force can break the flare nut.
14. When routing the line set between the outdoor
and indoor units:
A. Support the tubing adequately to avoid sags
that can trap the oil.
B. Isolate the tubing so it does not transmit
noise from vibration into the structure of the
building.
C. Avoid sharp edges that could cut the tubes.
D. Trap rises every 10 ft. (5-7m) with a ‘p’
trap, when outdoor unit mounted above the
indoor unit.
