Checking The Refrigerant Piping; To Check For Leaks; To Perform Vacuum Drying; Charging Refrigerant - Daikin ERHQ011BAV3 Installation Manual

If
The indoor unit is installed Install an oil trap every 10 m (height
higher than the outdoor difference).
unit
a Rising gas piping with oil trap
b Liquid piping
The outdoor unit is Oil traps are NOT required.
installed higher than the
indoor unit
4.3

Checking the refrigerant piping

4.3.1

To check for leaks

NOTICE
Do NOT exceed the unit's maximum working pressure (see
"PS High" on the unit name plate).
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.
4.3.2

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...
Does not change
Increases
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:
ERHQ+ERLQ011~016
Outdoor unit for air to water heat pump
4P385894-1 – 2015.05
Then
a
10 m
b
Then...
There is no moisture in the
system. This procedure is
finished.
There is moisture in the
system. Go to the next step.
▪ 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 To determine the additional refrigerant
amount
If the total liquid
piping length is...
≤10 m Do NOT add additional refrigerant.
>10 m R=(total length (m) of liquid
piping⁠ – ⁠ 1 0 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.
4.4.2

To charge refrigerant

WARNING
▪ Only use R410A as refrigerant. Other substances may
cause explosions and accidents.
▪ R410A contains fluorinated greenhouse gases. Its
global warming potential value is 2087.5. Do NOT vent
these gases into the atmosphere.
▪ When charging refrigerant, always use protective
gloves and safety glasses.
Prerequisite: Before charging refrigerant, make sure the refrigerant
piping is connected and checked (leak test and vacuum drying).
1 Connect the refrigerant cylinder to both the service port of the
gas stop valve and the service port of the liquid stop valve.
2 Charge the additional refrigerant amount.
3 Open the stop valves.
4.4.3 To fix the fluorinated greenhouse gases
label
1 Fill in the label as follows:
a From the multilingual fluorinated greenhouse gases label
peal off the applicable language and stick it on top of a.
b Factory refrigerant charge: see unit name plate
c Additional refrigerant amount charged
d Total refrigerant charge
2 Fix the label on the inside of the outdoor unit near the gas and
liquid stop valves.
4 Installation
Then...
a
b
c
d
Installation manual
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