Cautions For Necessity Of A Trap; Leak Test And Vacuum Drying; General Guidelines; Setup - Rotex RRLQ011CAV3 Manuel D'installation

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1 Compressor
2 Terminal cover
3 Indoor and outdoor field piping
4 Corking, etc.
5 Insulation material
6 Bolts
A Be careful with pipe, bolt and outer panel connections

10.3. Cautions for necessity of a trap

To avoid the risk of oil held inside the riser piping flowing back into the
compressor when stopped and causing liquid compression
phenomenon, or cases of deterioration of oil return, it will be
necessary to provide a trap at each difference in height of 10 m in the
riser gas piping.
■
Trap installation spacing. (See figure 4)
A Outdoor unit
B Indoor unit
C Gas piping
D Liquid piping
E Oiltrap
H Install trap at each difference in height of 10 m.
■
A trap is not necessary when the outdoor unit is installed at
higher position than the indoor unit.
RRLQ011~016CAV3+W1
Outdoor unit for air to water heat pump
4PW57794-1 – 10.2010
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A
11. L
EAK TEST AND VACUUM DRYING
When all piping work is complete and the outdoor unit is connected to
the indoor unit, it is necessary to:
■
check for any leakages in the refrigerant piping
■
to perform vacuum drying to remove all moisture in the
refrigerant piping.
If there is a possibility of moisture being present in the refrigerant
piping (for example, rainwater may have entered the piping), first
carry out the vacuum drying procedure below until all moisture has
been removed.

11.1. General guidelines

■
All piping inside the unit has been factory tested for leaks.
■
Use a 2-stage vacuum pump with a non-return valve which can
evacuate to a gauge pressure of –100.7 kPa (5 Torr absolute,
–755 mm Hg).
■
Connect the vacuum pump to both the service port of the gas
stop valve and the liquid stop valve to increase efficiency.
NOTICE
■
Do not purge the air with refrigerants. Use a vacuum
pump to evacuate the installation. No additional
refrigerant is provided for air purging.
■
Make sure that the gas stop valve and liquid stop
valve are firmly closed before performing the leak test
or vacuum drying.

11.2. Setup

(See figure 5)
1 Pressure gauge
2 Nitrogen
3 Refrigerant
4 Weighing machine
5 Vacuum pump
6 Stop valve

11.3. Leak test

The leak test must satisfy specification EN 378-2.
1 Vacuum leak test
1.1 Evacuate the system from the liquid and gas piping to
–100.7 kPa (5 Torr).
1.2 Once reached, turn off the vacuum pump and check that
the pressure does not rise for at least 1 minute.
1.3 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 0.2 MPa (2 bar).
Never set the gauge pressure higher than the maximum
operation pressure of the unit, i.e. 4.0 MPa (40 bar).
2.2 Test for leaks by applying a bubble test solution to all piping
connections.
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).
2.3 Discharge all nitrogen gas.
Installation manual
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