
Connection to the unit
n
Remove the cover panel from the outdoor unit
if necessary. It may be necessary to remove
the pre-cut bushings.
n
Take off the factory-fitted protective caps. You
can use the union nuts for additional mounting.
Make sure to slide the union nuts onto the pipe
before it is flared.
n
Make connections to the device by hand ini-
tially, in order to ensure a good fit. Later,
tighten the joints with two open-end wrenches
Use one wrench to resist the rotation of the
2
1
Fig. 47: Tighten fittings
1: Tighten 1st Spanner
2: Counter 2nd Spanner
Copper piping Out-
side diameter
Tightening torque
3/8" = 9,52 mm
32 - 40 Nm
5/8" = 15,88 mm
65 - 75 Nm
n
The installed refrigerant pipes, including the
flare connections, must be provided with suit-
able insulation.
n
Special measures need not be taken for the
return of the compressor oil.
NOTICE!
Use only tools which are approved for use in
an HVAC environment. (z. B.: bending pliers,
pipe/tubing cutters, de-burrers and flaring
tools). Do not cut refrigerant pipes with a saw.
NOTICE!
All work must be carried out in a way that pre-
vents dirt, particles, water etc. from entering,
refrigerant lines!
Outdoor units may be delivered with nuts suit-
able for joining flanges.
7.2 Commissioning the refrigera-
tion system
Leak testing
Once all the connections have been made, the
pressure gauge station is attached to the Schrader
valve as follows (if fitted):
blue = large valve = suction pressure
Once the connection has been made successfully,
the leak test is carried out with dry nitrogen. The
leak test involves spraying a leak detection spray
onto the connections. If bubbles are visible, the
connections have not been made properly. In that
case, tighten the connection or, if necessary,
create a new flange.
Pumping down to vacuum
After completing a successful leak test, the excess
pressure in the refrigerant pipes is removed and a
vacuum pump with an absolute final partial pres-
sure of min. 10 mbar is used to remove all of the
air and empty the pipes. Any moisture present in
the pipes will also be removed.
NOTICE!
A vacuum of at least 10 mbar must be pro-
duced!
45