Daikin VRV III REMQ72PBYD Engineering Data Download

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EDUS391004-N

Installation

Installation of Outdoor Units

NOTE

•

The air tight test and
vacuum drying should be
done using the service
ports of equalizer pipe,
gas pipe and liquid pipe
shutoff valve.
See the [R410A] Label
attached to the front plate
of the outdoor unit for
details on the location of
the service port (see
figure at right)

•

See

[Shutoff valve operation procedure]

“11-1 Before

working”

for details on handling the shutoff valve.

•

The refrigerant charge port is connected to unit pipe.
When shipped, the unit contains the refrigerant, so use caution
when attaching the charge hose.

<Air tight test>

Pressurize the liquid pipe, gas pipe, and equalizer pipe from the
service ports of each shutoff valve to 550 psi (do not pressurize
more than 550 psi). If the pressure does not drop within 24 hours,
the system passes the test.
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 liquid pipe and gas pipe shutoff
valve service ports by using a vacuum pump for more than 2 hours
and bring the system to –14.6 psi 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

If moisture might enter the piping, follow belows.
(I.e., if doing work during the rainy season, if the actual work
takes long enough that condensation may form on the inside of
the pipes, if rain might enter the pipes during work, etc.)

After evacuating the system for 2 hours, pressurize the system to 7.25
psi (vacuum break) with nitrogen gas and evacuate the system again
using the vacuum pump for 1 hour to –14.6 psi or less (vacuum
drying). If the system cannot be evacuated to –14.6 psi within 2 hours,
repeat the operation of vacuum break and vacuum drying.
Then, after leaving the system in vacuum for 1 hour, confirm that the
vacuum gauge does not rise.

PIPE INSULATION

•

Insulation of pipes should be done after performing “

8. AIR TIGHT

TEST AND VACUUM DRYING

”.

•

Always insulate the liquid piping, the gas piping, the equalizer pipe
(between the outdoor units for the outdoor multi system) and these
pipe connections.
Failing to insulate the pipes may cause leaking or burns.
And be sure to use the insulation which can withstand such
temperatures of 248°F or more for the equalizer pipe and the gas
piping.

•

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, humidity : 75% to 80% RH : min.
thickness : 9/16 in..



If the ambient temperature exceeds 86°F and the humidity 80%
RH, then the min. thickness is 3/4 in..
See the Engineering data book for detail.

•

If there is a possibility that condensation on the shutoff 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, etc., this must be prevented by caulking the connections, etc.

(Refer to figure 26)

•

The piping lead-out hole lid should be attached after opening a
knock hole.

(Refer to figure 27)

•

If small animals and the like might enter the unit through the piping
lead-out hole, close the hole with blocking material (procured on
site) after completion of “

11. ADDITIONAL REFRIGERANT

CHARGE AND CHECK OPERATION

”.

(Refer to figure 30)

(Refer to figure 26)

Insulation material

Caulking, etc.

(Refer to figure 27)

Piping lead-out hole lid

Open a knock hole at “

”.

Block “

”.

NOTE

•

After knocking out the holes, we recommend you remove burrs in
the knock holes (

See figure 27

) and paint the edges and areas

around the edges using the repair paint.

10. CHECKING OF DEVICE AND

INSTALLATION CONDITIONS

Be sure to check the followings.

For those doing electrical work

Make sure there is no faulty transmission wiring or loosing of a nut.
See “

7-4 Transmission Wiring Connection Procedure

”.

Make sure there is no faulty power wiring or loosing of a nut.
See “

7-5 Power Wiring Connection Procedure

”.

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

Make sure piping size is correct.
See “

6-1 Selection of piping material and Refrigerant branching kit

”.

Make sure insulation work is done.
See “

9. PIPE INSULATION”

Make sure there is no faulty refrigerant piping.
See “

6. REFRIGERANT PIPING

”.

11. ADDITIONAL REFRIGERANT CHARGE

AND CHECK OPERATION

The outdoor unit is charged with refrigerant when shipped from the
factory, but depending on the size and length of the piping when
installed, it may require additional charging.
For charging the additional refrigerant, follow the procedure in this
chapter.
And then carry out the check operation.

11-1 Before working

[About the refrigerant tank]

Check whether the tank has a siphon pipe before charging and place
the tank so that the refrigerant is charged in liquid form.
(See the figure below.)

NOTE

•

Always use the proper refrigerant (R410A). If charged with the refrigerant
containing an improper material, it may cause an explosion or accident.

•

R410A is a mixed refrigerant, so charging it as a gas will cause the
refrigerant composition to change, which may prevent normal operation.

[R410A] Label

With siphon pipe

Other tanks

Stand the tank upright and charge.
(The siphon pipe goes all the way inside,
so the tank does not need be put
upside-down charge in liquid form.)

Stand the tank upside-down and charge.

3P215731-10R