7 Installation
Installer reference guide
37
ERHQ+ERLQ011~016 + EHBH/X11+16CB
Daikin Altherma – Low temperature split
4P384974-1 – 2015.01
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.
INFORMATION
After opening the stop valve, it is possible that the pressure
in the refrigerant piping does NOT increase. This might be
caused by e.g. the closed state of the expansion valve in
the outdoor unit circuit, but does NOT present any problem
for correct operation of the unit.
7.6.5
To perform 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…
Then…
Does not change
There is no moisture in the
system. This procedure is
finished.
Increases
There is moisture in the
system. Go to the next step.
3
Evacuate for at least 2 hours to a pressure on the manifold of
−0.1 MPa (−1 bar).
4
After turning OFF the pump, 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.
7.7
Charging refrigerant
7.7.1
About charging refrigerant
The outdoor unit is factory charged with refrigerant, but in some
cases the following might be necessary:
What
When
Charging additional refrigerant
When the total liquid piping
length is more than specified
(see later).
Completely recharging refrigerant
Example:
▪ 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 The system is pumped down.
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. To do
so, use the internal service port of the outdoor unit
(between the heat exchanger and the 4‑way valve). Do
NOT use the service ports of the stop valves, because
vacuum drying cannot be performed properly from these
ports.
Typical workflow – Completely recharging refrigerant typically
consists of the following stages:
1 Determining how much refrigerant to charge.
2 Charging refrigerant.
3 Filling in the fluorinated greenhouse gases label, and fixing it to
the inside of the outdoor unit.
7.7.2
Precautions when charging refrigerant
INFORMATION
Also read the precautions and requirements in the
following chapters:
▪ General safety precautions
▪ Preparation
7.7.3
To determine the additional refrigerant
amount
If the total liquid
piping length is…
Then…
≤10 m
Do NOT add additional refrigerant.
>10 m
R=(total length (m) of liquid
piping–10 m)×0.054
R=Additional charge (kg)(rounded in units
of 0.1 kg)
INFORMATION
Piping length is the one way length of liquid piping.