Daikin SkyAir FHQ18PVJU, Installation Manual

Page: 28 / 94

11 English
Perform the following inspections securely after the
piping work.
Airtight test • - Make sure to use nitrogen gas. (For the
service port position, refer to the fi gure in “ Stop valve
operation method ”.)
[Procedure] Pressurize the air conditioner from the liquid
pipe and gas pipe up to 478 psi (Make sure not to exceed
478 psi). When the pressure does not drop for 24 hours, the
piping work shall be accepted.
If the pressure drops, check for leakage positions. (Confi rm
that there is no leakage, then release nitrogen.)
Vacuum drying • - Use a vacuum pump which can evacuate
up to –14.6 psi or less.
[Procedure] Operate the vacuum pump for evacuation for
2 hours or more using both liquid pipe and gas pipe until the
vacuum pressure reaches –14.6 psi or less. Leave the air
conditioner at –14.6 psi or less for 1 hour or more, and
confi rm that the vacuum pressure indicated by the vacuum
gage does not increase.
(If the vacuum pressure increases, the system may contain
moisture or have leakage.)
If there is a possibility of moisture remaining in the piping
(for example, when there is a possibility of dew condensation
inside the piping because the piping work was performed in
the rainy season or over a long period of time, or when rainwa-
ter may have entered the piping during the work)
Perform evacuation described above for 2 hours (vacuum
drying), pressurize the air conditioner up to 7 psi (vacuum
break) with nitrogen gas, then evacuate the air conditioner
using the vacuum pump for 1 hour to achieve –14.6 psi or less
(vacuum drying).
(If the vacuum pressure does not reach –14.6 psi or less even
after evacuation for 2 hours or more, repeat vacuum break and
vacuum drying.) Leave the air conditioner in the vacuum status
for 1 hour or more, and confi rm that the vacuum pressuree
indicated by the vacuum gauge does not increase.
Additional refrigerant charge 6-7
WARNING
To avoid injury always use protective gloves and eye protec- •
tion when charging refrigerant.
To avoid injury do not charge with unsuitable substances.
•
Use only the appropriate refrigerant.
NOTE
Refrigerant cannot be charged until fi eld wiring has been •
completed.
Refrigerant may only be charged after performing the air-
tight test and the vacuum drying (see above).
When charging refrigerant into the system, take care that its
maximum allowable charge is never exceeded, in view of the
danger of liquid hammer.
Refrigerant containers shall be opened slowly.
To avoid compressor breakdown, do not charge the refriger-
ant more than the specifed amount to raise the condensing
pressure.
This outdoor unit is factory charged with refrigerant. •
Charge the additional refrigerant calculated by the formula •
below.
Additional charging
amount =
Liquid piping length
× 0.036 +
Additional charging
depended on type
of indoor unit
(lb.) (ft.)×0.036 A (lb.)
Indoor unit
FAQ
FBQ
FCQ
FHQ
FTQ~PB
Additional charging
A (lb.)
0 0.35
Record the additional amount to the label stuck on the back of
front panel.
Charge the refrigerant to the liquid pipe in its liquid state. •
Since R410A is a mixed refrigerant, its composition changes
if charged in a state of gas and normal system operation
would no longer be assured.
Before fi lling, check whether the tank has a siphon attached
•
or not.
How to fi ll a tank with a siphon attached.
There is a siphon tube
inside, so there is no need
to turn the tank upside-down.
Fill with the tank upright.
Other ways of fi lling the tank
Fill with the tank upside-down.
After the vacuum drying is fi nished, charge the additional •
refrigerant in its liquid state through the liquid stop valve
service port.
Taking into account following instructions:
Check that gas and liquid stop valves are closed.
1.
Charge the specifi ed amount of refrigerant.
2.
If the outdoor unit is not in operation and the total amount •
cannot be charged, follow the procedures for additional
refrigerant charge shown below.
Make sure to use installation tools you exclusively use on
•
R410A installations to withstand the pressure and to prevent
foreign materials from mixing into the system.
Procedures for charging additional refrigerant.
•
Nitrogen
Dotted lines
represent
field piping
Cylinder
Stop valve service port
Vacuum pump
Weighing
scale
Charge hose
R410A
Pressure
reducing
valve
Outdoor unit
Indoor unit Liquid line Gas line
(Siphon system)
Valve A
See the “Cautions on service” label on the back of the front
panel for the settings for operation after replenishing refriger-
ant.
Open the gas line stop valve (leaving the liquid line stop 1.
valve, valve A in the diagram above, close) and perform the
operation to add the refrigerant.
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