Specifications

6
6 - Refrigerant circuit connections
Make piping runs as short as possible and avoid all unnecessa-
ry changes in direction or elevation.
To prevent heat loss, the two lines must be insulated sepa-
r a t e l y
Use an appropriate bending tool to form curves and avoid flatte-
ning the refrigerant tubes.
Fix piping with pipe clamps and make sure that any eventual
pipe vibrations cannot be transmitted to the building structure.
Use refrigeration quality piping only with an operating pressure
rating of at least 30 bars.
N e v e r use ordinary «plumbing» quality
piping :
you MUST use special de-oxidised, dehydrated, refrige-
rant quality copper piping.
Pipe lengths
• Maximum piping lengths
Note : Where the difference in elevation between the indoor
unit and the outdoor unit is greater than 5 metres, install
an oil trap every 5 metres.
The suction line must have a 2% gradient up to the compressor
Where piping lengths are unusually long and include a large
number of oil traps, it may be necessary to adjust the compres-
sor oil charge.
• Refrigerant charge to be added per extra 5 meter of
piping length
Refrigerant piping connections
(FLARE connections)
To avoid alteration of unit capacities, make sure that piping
lengths and changes in elevation are kept to a strict minimum.
Before connecting the refrigerant lines, follow the procedures
below (if pre-charged connection lines are not supplied) :
- Select copper pipe diameters according to the size of unit to
be installed.
- Install the refrigeration lines, making sure that no foreign
bodies get inside the piping.
- Install the flare connectors and flare the ends of the pipes.
- Evacuate the piping. This operation, which should last at least
15 minutes or even longer if there are large piping lengths and
changes in elevation, should be followed by a leak test. To this
effect, when the piping has been evacuated, close the pres-
sure guage tap, note the value on the guage, then wait for 15
minutes. If the needle moves, there is a leak in the system.
Make the necessary adjustments or repairs and repeat this
procedure until the needle no longer moves. For greater pre-
cision, use a vacuometer, or pressurise the installation with 25
bars of dry nitrogen.
- Open the service valves and top up the refrigerant charge if
necessary.
Minimum thickness 6 mm
Insulation
MOC-MOH 07 09 12 18 25 35 45 55
D (m) 1010 101015151515
L (m) 1515 151525252525
H (m) 7 7 7 7 10 10 10 10
on horizontal sections.
MOC-MOH 07 09 12 18 25 35 45 55
g/m 1515156565656565
MOC/MOH 25 G
R407C
Gas
Cooling
(suction)
Liquid
Cooling
Heat pump
(discharge)
Heat Pump
Heat pump
(discharge)
Gas
Cooling
( s u c t i o n )
Liquid
Cooling
High pressure
Manifold
Gas valve
Liquid valve
Pressure
tap
Low pressure
Gas line
Liquid line
Indoor unitOutdoor unit
L
L
H
D