Quick Start Manual
10
DVC/DVH Inverter 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. (Fig, 20)
2. Ductless mini-splits require both-liquid and 
suction-lines to be insulated.
3. Connections are made via are nuts.
4. The number of bends and length of refrigerant 
lines determine the pressure drop which affects 
capacity and efciency 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 nal 
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 are nut 
sizes recommended by the manufacturer.
• Insulate both lines with Amraex of equivalent 
with a wall thickness if at least 3/8”. Although 
the liquid line does not have to be insulated, it 
is recommended.
• Use copper tubing suitable to withstand 
pressures for R-410A refrigerant. We 
recommend a min. wall thickness of 0.027in. 
(0.7mm).
11. The tube size should always be the same 
diameter as the connections provided at the 
service valves of the outdoor unit.
 Note: On some models, a reducer or an 
expander may be shipped with the indoor 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 this part, should 
you discover that the outdoor units service valve 
sizes differ from the indoor unit. If this part is 
shipped with the indoor 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 are 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 
     indoor unit.
Refrigerant Piping
Model No.
DVC/DVH 09 DVC/DVH 12/18 DVC/DVH 24
Liquid Side-Gas Side Inch 1/4 - 3/8 1/4 - 1/2 3/8 - 5/8
Max. Refrigerant Pipe 
Length Unit Separation*
Ft. 
(m)
66 (20)
66 (20)/
82 (25)
82 (25)
Max. Level 
Difference/Vertical Lift**
Ft. 
(m)
26 (8)
26 (8)/
33 (10)
33 (10)
*Minimum pipe length must not be less that 10 feet.
** Trap rises every 10 feet (5-7m) with a ‘p’ trap when outdoor unit is mounted above 
the indoor unit.
Fig. 20










