Vacuum Drying; Pipe Insulation - Daikin KHRQ23M29H Installationsanleitung

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
–100.7 kPa.
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 0.05 MPa (0.5 bar) and repeat steps 1 to
3 until all moisture has been removed.
5 The outdoor stop valves can now be opened, and/or additional
refrigerant can be charged (see "13.4. Method for adding
refrigerant" on page 23).
INFORMATION
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.
NOTICE
The connections to the indoor units and all indoor units
should also be leak and vacuum tested. Keep the stop
valves of the indoor units open as well.
Refer to the indoor unit installation manual for more
details.
Leak test and vacuum drying should be done before the
power supply is set to the unit. If not, see "10.4. Leak test
and vacuum drying" on page 16 for more information.
REYAQ10~16P7Y1B
VRVIII system outdoor unit
4PW62582-1A – 08.2011
11. P
IPE INSULATION
After finishing the leak test and vacuum drying, the piping must be
insulated. Take into account the following points:
Make sure to insulate the connection piping and refrigerant
branch kits entirely.
Be sure to insulate liquid, suction, and HP/LP piping (for all
units).
Use heat resistant polyethylene foam which can withstand a
temperature of 70°C for liquid piping and polyethylene foam
which can withstand a temperature of 120°C for gas piping.
Reinforce the insulation on the refrigerant piping according to
the installation environment.
Ambient temperature
≤30°C
75% to 80% RH
>30°C
Condensation might form on the surface of the insulation.
If there is a possibility that condensation on the stop valve might
drip down into the indoor unit through gaps in the insulation and
piping because the outdoor unit is located higher than the indoor
unit, this must be prevented by sealing up the connections. See
below.
2
1
Humidity Minimum thickness
15 mm
≥80% RH
20 mm
1 Insulation material
2 Caulking, etc.
Installation manual
18