Leak Test; Vacuum Drying; Pipe Insulation; Selection Of Heat Insulation Materials - Daikin Altherma ERLQ018BAVJU Manuel D'installation

Leak test

1 Vacuum leak test
1.1 Fully open the gauge manifold's low-pressure valve (Lo)
and completely close its high-pressure valve (Hi). The high-
pressure subsequently requires no operation.
1.2 Evacuate the system from the gas piping to –14.6 psi
[–100.7 kPa (5 Torr, –755 mm Hg)].
1.3 Once reached, close the gauge manifold's low-pressure
valve (Lo), turn off the vacuum pump and check that the
pressure does not rise for about 4-5 minutes.
1.4 Should the pressure rise, the system may either contain
moisture (see vacuum drying below) or have leaks.
2 Pressure leak test
2.1 Break the vacuum by pressurizing with nitrogen gas to a
minimum gauge pressure of 29 psi [0.2 MPa (2 bar)].
Never set the gauge pressure higher than the maximum
operation pressure of the unit, i.e. 605 psi [4.17 MPa
(41.7 bar)].
2.2 Test for leaks by applying a bubble test solution to all piping
connections.
NOTE 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).
2.3 Discharge all nitrogen gas.

Vacuum drying

To remove all moisture from the system, proceed as follows:
1 Evacuate the system for at least 2 hours to a target vacuum of
–14.6 psi [–100.7 kPa (5 Torr, –755 mm Hg)].
2 Check that, with the vacuum pump turned off, the target vacuum
is maintained for at least 1 hour.
3 Should you fail to reach the target vacuum within 2 hours or
maintain the vacuum for 1 hour, the system may contain too
much moisture.
4 In that case, break the vacuum by pressurizing with nitrogen gas
to a gauge pressure of 7.25 psi [0.05 MPa (0.5 bar)] and repeat
steps 1 to 3 until all moisture has been removed.
5 The stop valves can now be opened, and/or additional
refrigerant can be charged (see "11.1. Additional refrigerant
charging" on page 11).
NOTE After opening the stop valve, it is possible that the
pressure in the refrigerant piping does not rise. 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.
ERLQ018~030BAVJU
Outdoor unit for air to water heat pump
4PW62590-1 – 07.2010

10.3. Pipe insulation

NOTE Any exposed piping may cause condensation or bruns
if touched.

Selection of heat insulation materials

When using commercial copper pipes and fittings, observe the
following:
Insulation material: polyethylene foam
Heat transfer rate: 0.285~0.361 BTU.inch/h.ft
W/m•K)
Refrigerant gas pipe's surface temperature reaches 230°F
(110°C) max.
Choose heat insulation materials that will withstand this
temperature.
Be sure to insulate both the gas and liquid piping and to provide
insulation dimensions as below.
Connection pipe Inner diameter
1/4 inch 0.31~0.39 inch
(Ø6.4 mm)
5/8 inch 0.63~0.79 inch
(Ø15.9 mm) (16~20 mm)
If the temperature is higher than 86°F (30°C) and the humidity is
higher than RH 80%, then the thickness of the sealing materials
should be at least 0.79 inch (20 mm) in order to avoid
condensation on the surface of the sealing.
2
1
6
5
Use separate thermal insulation pipes for gas and liquid
refrigerant pipes.
11. C
HARGING REFRIGERANT
DANGER: ELECTRICAL SHOCK
See "4. General safety precautions" on page 3.
Refrigerant cannot be charged until field wiring has been
completed.
Refrigerant may only be charged after performing the leak test
and the vacuum drying.
When charging a system, care shall be taken that its maximum
permissible charge is never exceeded, in view of the danger of
liquid hammer.
Charging with an unsuitable substance may cause explosions
and accidents, so always ensure that the appropriate refrigerant
R410A is charged.
Refrigerant containers shall be opened slowly.
Always use protective gloves and protect your eyes when

charging refrigerant.

When the refrigerant system is to be opened, refrigerant must
be treated according to the applicable legislation.
2
.°F (0.041~0.052
Pipe insulation
Thickness
≥0.39 inch
(8~10 mm) (10 mm)
≥0.51 inch
(13 mm)
1 Gas pipe
2 Conduit including
interunit wiring
3
3 Liquid pipe
4
4 Liquid pipe insulation
5 Finishing tape
6 Gas pipe insulation
Installation manual
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