10
GB
15. Please do not use a corrosion inhibitor in the water system.
16. When installing the HBC unit in an environment which may drop below 0°C,
please add antifreeze (Propylene Glycol only) to the circulating water.
5.3. Water treatment and quality 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 scale, 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 sys-
tem.
•
Removing of foreign objects or impurities within the pipes.
During installation, make sure that foreign objects, such as welding fragments,
sealant particles, or rust, do not enter the pipes.
•
Water Quality Processing
2
Water quality standard
6. Electrical work
Consult all related regulations and power companies beforehand.
Warning:
Electrical work should be handled by qualified electrical engineers in accord-
ance with all related regulations and attached instruction manuals. Special cir-
cuits should also be used. If there is a lack of power capacity or a deficiency in
electrical work, it may cause a risk of electric shock or fire.
Connect all wires securely.
•
Fix power source wiring to control box by using buffer bushing for tensile force
(PG connection or the like).
[Fig. 6.0.1] (P.4)
Never connect the power cable to the terminal board for control cables.
(Otherwise it may be broken.)
Be sure to wire between the control wire terminal boards for indoor unit,
outdoor unit and HBC controller.
Use non-polarized 2-wire as transmission cables.
Use 2-core shielding cables (CVVS, CPEVS) of more than 1.25 mm
2
in diameter as
transmission cables.
The switch capacity of the main power to BC controllers and the wire size are as fol-
lows:
•
For other detailed information, refer to the outdoor unit installation manual.
•
Power supply cords of appliances shall not be lighter than design 245 IEC 53 or
227 IEC 53.
•
A switch with at least 3 mm contact separation in each pole shall be provided by
the Air conditioner installation.
Caution:
Do not use anything other than the correct capacity fuse and breaker. Using
fuse, conductor or copper wire with too large capacity may cause a risk of mal-
function or fire.
Ensure that the outdoor units are put to the ground. Do not connect the earth
cable to any gas pipe, water pipe, lightening rod or telephone earth cable. In-
complete grounding may cause a risk of electric shock.
7. Setting addresses and operating units
The address switch of each HBC controller is set to “000” when shipped from the fac-
tory.
•
Set the address switch to 1 + the address of the outdoor unit.
The HBC controller address should generally be set to 1 + the address of
the outdoor unit. However, if this would result in it having the same
address as another outdoor unit, set the address between 51 and 100,
making sure that it is different from the address of other controllers.
•
Please refer to the outdoor unit installation manual.
1
Depending on the quality of the cold-temperature water used in the aircondi-
tioner, 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/
ℓ
.
Items
Low to mid-range
temperature water system
Tendency
Recirculating
water
[20<T<60°C]
[68<T<140°F]
Make-up
water
Corrosive
Scale-
forming
pH (25°C) [77°F]
7.0 ~ 8.0
7.0 ~ 8.0
Electric conductivity
(mS/m) (25°C) [77°F]
30 or less
[300 or less]
30 or less
[300 or less]
(µ s/cm) (25°C) [77°F]
Chloride ion
(mg Cl-/
ℓ
)
50 or less
50 or less
Sulfate ion
(mg SO4
2-
/
ℓ
)
50 or less
50 or less
Acid consumption (pH4.8)
50 or less
50 or less
(mg CaCO
3
/
ℓ
)
Total hardness
(mg CaCO
3
/
ℓ
)
70 or less
70 or less
Calcium hardness
(mg CaCO
3
/
ℓ
)
50 or less
50 or less
Ionic silica
(mg SiO
2
/
ℓ
)
30 or less
30 or less
Iron
(mg Fe/
ℓ
) 1.0 or less 0.3 or less
Copper
(mg Cu/
ℓ
) 1.0 or less 0.1 or less
Sulfide ion
(mg S
2-
/
ℓ
)
not to be
detected
not to be
detected
Ammonium ion
(mg NH
4
+
/
ℓ
) 0.3 or less 0.1 or less
Residual chlorine
(mg Cl/
ℓ
) 0.25 or less 0.3 or less
Free carbon dioxide
(mg CO
2
/
ℓ
) 0.4 or less 4.0 or less
Ryzner stability index
6.0 ~ 7.0
–
Reference : Guideline of Water Quality for Refrigeration and Air Conditioning
Equipment. (JRA GL02E-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), first conduct a water quality anal-
ysis 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, adjust water quality before replacing
the unit.
S
tan
dard
it
ems
R
e
fe
re
nc
e i
te
m
s
A
Control box
B
Power source wiring
C
ø21 hole (closed rubber bushing)
D
Transmission wiring
E
Clip cables here
Switch (A)
Molded case
circuit breaker
Earth leakage
breaker
Wire size
Capacity
Fuse
16
16
20 A
20 A 30 mA
0.1 s or less
1.5 mm
2
WT06421X02.book Page 10 Wednesday, April 25, 2012 8:43 AM
