GB
Connecting
Z
ater pipes
A
Indoor unit
B
Water pipe: From HBC unit
C
Water pipe: To HBC unit
D
Strainer (4 mesh or more)
( eld supply)
E
Shut off valve
( eld supply)
A
To outdoor unit
B
End connection (brazing)
C
HBC controller
D
Indoor unit
E
Twinning pipe ( eld supply)
F
Up to three units for 1 branch hole; total capacity: below
(but in same mode, cooling heating)
Fig
-
Fig
-
D
D
D
D
D
F
D
A B
E
*1
C
Water pipework is screw
connections
9. HBC water pipe connection sizes
Unit model
Connection size
Pipe size
Water
volume ( )
Water
inlet
Water
outlet
Water
out
Water
return
PLF -WP32 BM
Rc 3 4
screw
Rc 3 4
screw
Inner
diameter
2 mm
Inner
diameter
2 mm
1.5
PLF -WP4
BM
1.5
PLF -WP5
BM
1.5
1 . Please refer to the [Fig. 4-4] when connecting the water supply.
11. Install a shut off valve and strainer in a place that is easy to operate and makes
maintenance work easy.
12. Apply insulation to the indoor unit pipework, strainer, shut off valve, and pressure
reducing valve.
13. Please do not use a corrosion inhibitor in the water system.
Water treat
P
ent and
T
ualit
\
control
To preserve water quality, use the closed type of water circuit. When the circulating
water quality is poor, the water heat exchanger can develop scales, leading to a
reduction in heat-exchange power and possible corrosion. Pay careful attention to
water processing and water quality control when installing the water circulation system.
Removing of foreign ob ects or impurities within the pipes.
During installation, make sure that foreign ob ects, such as welding fragments,
sealant particles, or rust, do not enter the pipes.
Water Quality Processing
1
Depending on the quality of the cold-temperature water used in the airconditioner,
the copper piping of the heat exchanger may corrode.
Regular water quality processing is recommended.
If a water supply tank is installed, keep air contact to a minimum, and keep the
level of dissolved oxygen in the water no higher than 1mg .
2
Water quality standard
Items
Low to mid-range
temperature water
system
Tendency
Recirculating
water
[2 T 6 C]
[6 T 14 F]
Make-up
water
Corrosive
Scale-
forming
Standard items
pH (25 C) [77 F]
7. .
7. .
Electric conductivity
3 or less
[3 or
less]
3 or less
[3 or
less]
(mS m) (25 C) [77 F]
( s cm) (25 C) [77 F]
Chloride ion
(mg Cl- ) 5 or less 5 or less
Sulfate ion
(mg SO4
2
- ) 5 or less 5 or less
Acid consumption (pH4. )
5 or less 5 or less
(mg CaCO
3
)
Total hardness
(mg CaCO
3
) 7 or less 7 or less
Calcium hardness
(mg CaCO
3
) 5 or less 5 or less
Ionic silica
(mg SiO
2
) 3 or less 3 or less
Reference items
Iron
(mg Fe ) 1. or less .3 or less
Copper
(mg Cu ) 1. or less .1 or less
Sul de ion
(mg S
2
- ) not to be
detected
not to be
detected
Ammonium ion
(mg NH4
) .3 or less .1 or less
Residual chlorine
(mg Cl ) .25 or less .3 or less
Free carbon dioxide
(mg CO
2
) .4 or less 4. or less
Ryzner stability inde
6. 7.
–
Reference : Guideline of Water Quality for Refrigeration and Air Conditioning
Equipment. ( RA GL 2E-1994)
3
Consult with a specialist about water quality control methods and calculations
before using anti-corrosive solutions.
4
When replacing a previously installed air conditioning device (even when only
the heat exchanger is being replaced), rst conduct a water quality analysis and
check for possible corrosion.
Corrosion can occur in cold-water systems even if there has been no prior signs
of corrosion.
If the water quality level has dropped, ad ust water quality before replacing the
unit.
C
B
E
A
D
E
Note:
Connection o
I
P
ultiple indoor units
Z
ith one connection (or
M
oint pipe)
Total capacity of connectable indoor units: Less than
Number of connectable indoor units: Maximum 3 Sets
Selection of water piping
Select the size according to the total capacity of indoor units to be installed
downstream.
Please group units that operate on 1 branch.
