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7 Installation
Installer reference guide
38
ERLQ004~008CA + 26CB6W
Daikin Altherma – Low temperature split
4P449978-1B – 2018.07
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
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
Be sure to open the gas stop valve after piping installation
and vacuuming. Running the system with the valve closed,
the compressor may break down.
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.
7.7
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 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.
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)×0.020
R=Additional charge (kg) (rounded in units
of 0.1 kg)
INFORMATION
Piping length is the one-way length of liquid piping.
7.7.4
To determine the complete recharge
amount
INFORMATION
If a complete recharge is necessary, the total refrigerant
charge is: the factory refrigerant charge (see unit name
plate) + the determined additional amount.
7.7.5
To charge additional refrigerant
WARNING
▪ Only use R410A as refrigerant. Other substances may
cause explosions and accidents.
▪ R410A contains fluorinated greenhouse gases. Its
global warming potential (GWP) value is 2087.5. Do
NOT vent these gases into the atmosphere.
▪ When charging refrigerant, always use protective
gloves and safety glasses.
CAUTION
To avoid compressor breakdown, do NOT charge more
than the specified amount of refrigerant.
Prerequisite:
Before charging refrigerant, make sure the refrigerant
piping is connected and checked (leak test and vacuum drying).
1
Connect the refrigerant cylinder to the service port.
2
Charge the additional refrigerant amount.
3
Open the gas stop valve.