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NOTICE
Make sure to use a recommended bubble test solution
from your wholesaler. Do not use soap water, which may
cause cracking of flare nuts (soap water may contain salt,
which absorbs moisture that will freeze when the piping
gets cold), and/or lead to corrosion of flared joints (soap
water may contain ammonia which causes a corrosive
effect between the brass flare nut and the copper flare).
1 Charge the system with nitrogen gas up to a gauge pressure of
at least 200 kPa (2 bar). It is recommended to pressurize to
3000 kPa (30 bar) in order to detect small leaks.
2 Check for leaks by applying the bubble test solution to all
connections.
3 Discharge all nitrogen gas.
4.3.3
To perform vacuum drying
NOTICE
▪ Connect the vacuum pump to both the service port of
the gas stop valve and the service port of the liquid
stop valve to increase efficiency.
▪ Make sure that the gas stop valve and liquid stop valve
are firmly closed before performing the leak test or
vacuum drying.
1 Vacuum the system until the pressure on the manifold indicates
−0.1 MPa (−1 bar).
2 Leave as is for 4-5 minutes and check the pressure:
If the pressure...
Does not change
Increases
3 Vacuum the system for at least 2 hours to a manifold pressure
of −0.1 MPa (−1 bar).
4 After turning the pump OFF, check the pressure for at least
1 hour.
5 If you do NOT reach the target vacuum or CANNOT maintain
the vacuum for 1 hour, do the following:
▪ Check for leaks again.
▪ Perform vacuum drying again.
NOTICE
Make sure to open the stop valves after installing the
refrigerant piping and performing vacuum drying. Running
the system with the stop valves closed may break the
compressor.
4.4
Charging refrigerant
4.4.1
About charging refrigerant
The outdoor unit is factory charged with refrigerant, but in some
cases the following might be necessary:
What
Charging additional refrigerant
Completely recharging refrigerant Example:
Then...
There is no moisture in the
system. This procedure is
finished.
There is moisture in the
system. Go to the next step.
When
When the total liquid piping
length is more than specified
(see later).
▪ When relocating the system.
▪ After a leak.
Charging additional refrigerant
Before charging additional refrigerant, make sure the outdoor unit's
external refrigerant piping is checked (leak test, vacuum drying).
INFORMATION
Depending on the units and/or the installation conditions, it
might be necessary to connect electrical wiring before you
can charge refrigerant.
Typical workflow – Charging additional refrigerant typically consists
of the following stages:
1 Determining if and how much you have to charge additionally.
2 If necessary, charging additional refrigerant.
3 Filling in the fluorinated greenhouse gases label, and fixing it to
the inside of the outdoor unit.
Completely recharging refrigerant
Before completely recharging refrigerant, make sure the following is
done:
1 All refrigerant is recovered from the system.
2 The outdoor unit's external refrigerant piping is checked (leak
test, vacuum drying).
3 Vacuum drying on the outdoor unit's internal refrigerant piping is
performed.
NOTICE
Before completely recharging, perform vacuum drying on
the outdoor unit's internal refrigerant piping as well.
NOTICE
To perform vacuum drying or a complete recharge of the
outdoor unit's internal refrigerant piping it is necessary to
activate the vacuum mode (see
vacuum mode field setting" on page
required valves in the refrigerant circuit so the vacuuming
process or recharge of refrigerant can be done properly.
▪ Before vacuum drying or recharging, activate field
setting "vacuum mode".
▪ After finishing vacuum drying or recharging, deactivate
field setting "vacuum mode".
WARNING
Some sections of the refrigerant circuit may be isolated
from other sections caused by components with specific
functions (e.g. valves). The refrigerant circuit therefore
features additional service ports for vacuuming, pressure
relief or pressurizing the circuit.
In case it is required to perform brazing on the unit, ensure
that there is no pressure remaining inside the unit. Internal
pressures need to be released with ALL the service ports
indicated on the figures below opened. The location is
depending on model type.
25
"To activate/deactivate the
12) which will open
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