Mitsubishi Electric PKFY-WL-VLM Series, Руководство по установке

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en
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Water quality standard
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
Standard items
pH (25°C) [77°F] 7.0 ~ 8.0 7.0 ~ 8.0
Electric conductivity
30 or less
[300 or
less]
30 or less
[300 or
less]
(mS/m) (25°C) [77°F]
(μS/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
Reference items
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 NH4+/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 inde 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 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, adjust water quality before replacing the unit.
4. Connecting water pipes
A
To outdoor unit
B
End connection
C
Hydro unit without valve
D
To main piping
E
Indoor unit without valve
E
´ Indoor unit with valve
F
Auto air vent valve (Highest
point on the water pipe)
(supplied)
G
Optional VALVE KIT
H
Pipe length between indoor
unit without valve and optional
VALVE KIT is less than 5m.
Fig. 4-6
A
C
D
B
F
G
E
G
E E ´ E ´
H
4.1.4. Water pipe insulation for connection with hydro unit
1. Cold (hot) water pipes require thermal insulation to prevent condensation on the
pipe surface while especially in the cooling mode as well as heat emission from
and penetration into the pipes.
2. Be sure to add insulation work to water piping by covering water pipework
separately with enough thickness heat-resistant polyethylene, so that no gap is
observed in the joint between indoor unit and insulating material, and insulating
materials themselves. When insulation work is insufficient, there is a possibility of
condensation, etc. Pay special attention to insulation work in the ceiling plenum.
(Fig. 4-1, Fig. 4-2)
• Insulation materials for the pipes to be added on site must meet the following
specifications:
Branch piping for indoor unit or
VALVE KIT
20 mm or more
• This specification is based on copper for water piping. When using plastic
pipework, choose a thickness based on the plastic pipe performance.
• Thermal insulation materials should have a thickness of 20 mm or larger.
• Install a heater on site when pipes are installed outside where a temperature is
0°C or below and when the breaker may be turned off.
• Installation of pipes in a high-temperature high-humidity environment, such as
the top floor of a building, may require the use of insulation materials thicker than
the ones specified in the chart above.
• When certain specifications presented by the client must be met, ensure that
they also meet the specifications on the chart above.
3. Expansion vessel
Connect an expansion vessel to the expansion vessel connection port of the
hydro unit or to the return water pipe.
• Install an expansion vessel to accommodate expanded water.
• The maximum water temperature is 60°C.
• The minimum water temperature is 5°C.
• The circuit protection valve set pressure is 0.8-0.96 MPa.
• The circulation pump head pressure is 0.2 MPa. (CMH-WM250/350/500V-A)
4. Leakproof the water pipework, valves and drain pipework. Leakproof all the way to,
and include pipe ends so that condensation cannot enter the insulated pipework.
5. Apply caulking around the ends of the insulation to prevent condensation getting
between the pipework and insulation.
6. Add a drain valve so that the unit and pipework can be drained.
7. Ensure there are no gaps in the pipework insulation. Insulate the pipework right up
to the unit.
8. Ensure that the gradient of the drain pan pipework is such that discharge can only
blow out.
9. Hydro unit and VALVE KIT water pipe connection sizes and pipe sizes.
Unit model
Connection size Pipe size
Water
volume (ℓ)
Water inlet Water outlet Water out Water return
PKFY-WL10VLM
Rc 3/4
screw
Rc 3/4
screw
I.D.
≥ 20.0 mm
I.D.
≥ 20.0 mm
0.6
PKFY-WL15VLM
PKFY-WL20VLM
0.7
PKFY-WL25VLM
PKFY-WL32VLM
1.0
PKFY-WL40VLM 1.1
10. Please refer to the [Fig. 4-1] 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.
4.1.5. 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 form 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 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
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/ℓ.
* If the length of branched water piping on WL40 equals or exceeds 40 m, use pipes
with an inner diameter of 30 mm or larger.
* PKFY-WL · VLM series has no valve
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