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3P362438-5N English
If there is a pressure drop, check for leaks, make repairs and perform
the air tight test again.
<Vacuum drying>
Evacuate the system from the suction gas pipe, high/low pressure gas
pipe and liquid pipe stop valve service ports by using a vacuum pump
for more than 2 hours and bring the system to 500 microns or less.
After keeping the system under that condition for more than 1 hour,
check if the vacuum gauge rises or not. If it rises, the system may
either contain moisture inside or have leaks.
NOTE
During the rainy season, moisture might enter the piping . If
working during a rainy season and the work takes long enough
for condensation to form inside the pipes, take the following
precautions:
After evacuating the system for 2 hours, pressurize the system to
375,000 microns (vacuum break) with nitrogen gas and evacuate the
system again using the vacuum pump for 1 hour to 500 microns or
less (vacuum drying).
If the system cannot be evacuated to 500 microns within 2 hours,
repeat the operation of vacuum break and vacuum drying.
Then, after leaving the system in a vacuum for 1 hour, confirm that the
vacuum gauge does not rise.
11 . Pipe insulation
NOTE
Pipe insulation thickness provided below are guidelines only. Pipes
must be insulated with the appropriate thickness of insulation per ap-
plicable local/state or national codes.
•
Insulation of pipes should be done after performing 10. Air tight test
and vacuum drying on page 23.
•
Always insulate the suction gas pipe, high/low pressure gas pipe,
liquid pipe and pipe connections.
•
Failing to insulate the pipes may cause leaking or burns.
Be sure to use insulation designed for HVAC equipment.
•
Reinforce the insulation on the refrigerant piping according to the
installation environment. Condensation might form on the surface of
the insulation. Refer to the below.
-
Ambient temperature : 86°F (30°C), humidity : 75% to 80% RH :
minimum thickness : 9/16 in. (15 mm).
-
If the ambient temperature exceeds 86°F (30°C) and the humidity
80% RH, then the minimum thickness is 3/4 in. (20 mm).
See the Engineering Data Book for detail.
•
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 caulking the connections. (Refer to
the following figure.)
3
4
5
1
6
1
2
1 Insulation material
2 Caulking, etc.
3 Liquid pipe stop valve
4 Suction gas pipe stop
valve
5 High/low pressure gas
pipe stop valve
6 Connection pipe
12 . Checking of device and installation conditions
Be sure to check the followings.
For those doing electrical work
1
Make sure there is no faulty transmission wiring or loosening of a
nut.
See 9.4. Transmission wiring connection procedure on page 20.
2
Make sure there is no faulty power wiring or loosening of a nut.
See 9.5. Power wiring connection procedure on page 21.
3
Has the insulation of the main power circuit deteriorated?
Measure the insulation and check the insulation is above regular
value in accordance with relevant local and national regulations.
For those doing pipe work
1
Make sure piping size is correct.
See 7.2. Selection of piping material on page 9 and 7.4. Selection of
refrigerant branch kits on page 10.
2
Make sure insulation work is done.
See 11. Pipe insulation.
3
Make sure there is no faulty refrigerant piping.
See 8. Precautions on refrigerant piping on page 14.
13 .
Making field settings
To continue the configuration of the outdoor units, it is required to give
some input to the printed circuit board of the unit. This chapter will
describe how manual input is possible by operating the push buttons/
DIP switches on the printed circuit board and reading the feedback
from the 7 segment displays.
For VRV IV REYQ-T series it is alternatively possible to make several
commissioning field settings through a personal computer interface
(for this, option 999482P3 is required). The installer can prepare the
configuration (off-site) on PC and afterwards upload the configuration
to the system. How to connect the cable is described in
13.3. Connecting the PC configurator to the outdoor unit on page 26.
The contents of the actual settings is discussed and explained in 15.2.
Monitoring function and field settings on page 33.
13 .1 . Accessing the push buttons on the printed circuit
board
It is not required to open the complete control box to access the
push buttons on the printed circuit board and read out the 7 segment
display (s).
To access you can remove the front panel (see figure). Now you can
open the inspection door of the control box cover (see figure). You can
see 3 push buttons and 3 seven-segment displays and DIP switches.
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