Daikin LRMEQ4BY1, Инструкция по установке и эксплуатации

Страница: 20 / 44

6 Installation
Installer and user reference guide
20
LRMEQ+4BY1
Air-cooled refrigeration condensing unit
4P500362-1A – 2018.09
≤30°
A
A
a
b
c
a Joint for branching
b Header
c Downward piping
Gas piping branching
▪ Install branched piping above main piping. This will prevent
refrigerant oil from flowing back to non‑operating indoor units.
a b
a Main piping
b Joint for branching
▪ Make sure the "horizontal" gas piping (and refnet header) slopes
down to the outdoor unit.
a b c
a Gas piping sloping down from indoor units to branching
b T-joint for branching
c Gas piping sloping down from branching to outdoor unit
a b
c
a Joint
b Branch pipe
c Main pipe
▪ If the outdoor unit is located higher than the indoor units, include
oil traps in the piping at 5 m intervals from the outdoor unit. This
will ensure the smooth returning of oil in the piping slanting
upward.
Liquid and gas piping
▪ Insulate the refrigerant branching. Make sure the thickness of the
refrigerant branching insulation equals that of the refrigerant
piping insulation.
6.5 Checking the refrigerant piping
6.5.1 About checking the refrigerant piping
Checking the refrigerant piping involves:
▪ Checking for any leakages in the refrigerant piping.
▪ Performing vacuum drying to remove all moisture, air or nitrogen
in the refrigerant piping.
If there is a possibility of moisture being present in the refrigerant
piping (for example, water may have entered the piping), first carry
out the vacuum drying procedure below until all moisture has been
removed.
All piping inside the unit has been factory tested for leaks.
Only field installed refrigerant piping needs to be checked.
Therefore, make sure that all the outdoor unit stop valves are firmly
closed before performing leak test or vacuum drying.
NOTICE
Make sure that all (field supplied) field piping valves are
OPEN (not outdoor unit stop valves!) before you start leak
test and vacuuming.
For more information on the state of the valves, refer to
"6.5.3 Checking refrigerant piping: Setup" on page 20 .
6.5.2 Checking refrigerant piping: General
guidelines
Connect the vacuum pump through a manifold to the service port of
all stop valves to increase efficiency (refer to
"6.5.3 Checking
refrigerant piping: Setup" on page 20 ).
NOTICE
Use a 2-stage vacuum pump with a non-return valve or a
solenoid valve that can evacuate to a gauge pressure of
–⁠100.7 kPa (−⁠1.007 bar)(5 Torr absolute).
NOTICE
Make sure the pump oil does not flow oppositely into the
system while the pump is not working.
NOTICE
Do not purge the air with refrigerants. Use a vacuum pump
to evacuate the installation.
6.5.3 Checking refrigerant piping: Setup
p< p>
N2
C
b c e
a
g
f
d
A B
a Pressure reducing valve
b Nitrogen
c Weighing scales
d Refrigerant R410A tank (siphon system)
e Vacuum pump
f Liquid line stop valve
g Gas line stop valve
A Valve A
B Valve B
C Valve C
Valve State of valve
Valve A Open
Valve B Open
Valve C Open
Liquid line stop valve Close
Gas line stop valve Close
NOTICE
Indoor units should also be leak and vacuum tested. Keep
any possible (field supplied) field piping valves open as
well.
6.5.4 To perform a leak test
The leak test must satisfy the specifications of EN378‑2.