Mitsubishi Electric CITY MULTI PEFY-WL06NMAU-A Manual De Instalación página 13

7. Connecting water pipe
Please observe the following precautions during installation.
7.1. Important notes on water pipework
installation
• The water pressure resistance of the water pipes in the heat source unit is 1.0
MPa [145 psi].
• Please connect the water pipework of each indoor unit to the correct port on the
HBC. Failure to do so will result in incorrect running.
• Please list the indoor units on the naming plate in the HBC unit with addresses
and end connection numbers.
• If the number of indoor units are less than the number of ports on the HBC, the
unused ports can be capped. Without a cap, water will leak.
• Use the reverse-return method to insure proper pipe resistance to each unit.
• Provide some joints and bulbs around inlet/outlet of each unit for easy
maintenance, checkup, and replacement.
Install a suitable air vent on the water pipe. After flowing water through the pipe,
•
vent any excess air.
Secure the pipes with metal fitting, positioning them in locations to protect pipes
•
against breakage and bending.
• Do not confuse the water intake and outlet piping. Error code 5102 will appear
on the remote controller if a test run is performed with the pipework installed
incorrectly (inlet connected to outlet and vice versa).
• This unit doesn't include a heater to prevent freezing within tubes. If the water
flow is stopped on low ambient, drain the water out.
• The unused knockout holes should be closed and the refrigerant pipes, water
pipes, power source and transmission wires access holes should be filled with
putty.
Install water pipe so that the water flow rate will be maintained.
•
• Wrap sealing tape as follows.
1 Wrap the joint with sealing tape following the direction of the threads
(clockwise), do not wrap the tape over the edge.
2 Overlap the sealing tape by two-thirds to three-fourths of its width on each
turn. Press the tape with your fingers so that it is tight against each thread.
3 Do not wrap the 1.5th through 2nd farthest threads away from the pipe end.
• If there is a risk of freezing, carry out a procedure to prevent it.
• When connecting heat source unit water piping and on site water piping, apply
liquid sealing material for water piping over the sealing tape before connection.
• Do not use steel pipes as water pipes.
- Copper pipes are recommended.
• Install a strainer (40 mesh or more) on the pipe next to the valve to remove the
foreign matters.
• Be sure to provide anti-dew condensation treatment on the inlet and outlet of
the water pipes and on the valve. Provide an appropriate treatment on the end
surface of the dew proofing material to keep condensation out.
• When water has been supplied to the water pipework, purge the system of
air. The details of air purging can be found separately in the water circuit
maintenance manual.
Leave the pipe-holding sheet metal as it is ([Fig. 7.2.2] Ⓒ). If the pipe is
•
connected without the sheet metal in place, undue force may be applied to the
pipe, and the pipe may become deformed.
• Be sure to braze the water pipes after covering a wet cloth to the insulation
pipes of the units in order to prevent them from burning and shrinking by
heat.
• Install the unit so that external force is not applied to the water pipes.
7.2. Water pipe insulation
1. Connect the water pipes of each indoor unit to the same (correct) end connection
numbers as indicated on the indoor unit connection section of each HBC unit. If
connected to wrong end connection numbers, there will be no normal operation.
2. List indoor unit model names in the name plate on the HBC unit control box (for
identification purposes), and HBC unit end connection numbers and address
numbers in the name plate on the indoor unit side.
Seal unused end connections using cover caps (sold separately). Not replacing
on end cap will lead to water leakage.
3. 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. 7.2.1] (P.6)
A Locally procured insulating material for pipes
B Bind here usin g band or tape.
C Do not leave any opening.
D Lap margin: more than 40 mm
E Insulating material (field supply)
F Unit side insulating material
G Depending on the type of joint selected, a gap may be left between the pipe cover on
the unit side and the joint. If this is the case, fill the gap with another pipe cover (not
supplied).
[Fig. 7.2.2] (P.6)
A Water pipe: To HBC unit
B Water pipe: From HBC unit
C Pipe-holding sheet metal
• Insulation materials for the pipes to be added on site must meet the following
specifications:
HBC unit
20 mm [13/16 in] or more
-indoor unit
This specification is based on copper for water piping. When using plastic
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pipework, choose a thickness based on the plastic pipe performance.
• 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
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they also meet the specifications on the chart above.
4. Expansion vessel
Install an expansion vessel to accommodate expanded water. (circuit protection
valve set pressure: 600 kPa [87 psi])
Expansion vessel selection criteria:
• The water containment volume of the HBC.
• The maximum water temperature is 60°C [140°F].
• The minimum water temperature is 5°C [41°F].
• The circuit protection valve set pressure is 370-490 kPa [53-71 psi].
• The circulation pump head pressure is 0.24 MPa [35 psi].
5. 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.
6. Apply caulking around the ends of the insulation to prevent condensation getting
between the pipework and insulation.
7. Add a drain valve so that the unit and pipework can be drained.
8. Ensure there are no gaps in the pipework insulation. Insulate the pipework right
up to the unit.
9. Ensure that the gradient of the drain pan pipework is such that discharge can
only blow out.
10. HBC water pipe connection sizes
Connection size
Model name
Water inlet
PEFY-WL06NMAU-A
PEFY-WL08NMAU-A
PEFY-WL12NMAU-A
PEFY-WL15NMAU-A
PEFY-WL18NMAU-A
O.D.
22 mm
PEFY-WL24NMAU-A
PEFY-WL27NMAU-A
PEFY-WL30NMAU-A
PEFY-WL36NMAU-A
PEFY-WL48NMAU-A
[Fig. 7.2.3] (P.6)
A To outdoor unit
B End connection (brazing)
C HBC unit
D Indoor unit
E Twinning pipe (field supply)
F Up to three units for 1 branch hole; total capacity: below 30 (but in same mode,
cooling/heating)
Note:
*1 Connection of multiple indoor units with one connection (or joint pipe)
• Total capacity of connectable indoor units: Less than 30
• Number of connectable indoor units: Maximum 3 Sets
Pipe size
Water
Water Water
volume (ℓ)
Water out
outlet return
I.D. I.D.
≥ 20 mm ≥ 20 mm
[13/16 in] [13/16 in]
O.D.
22 mm
I.D. I.D.
≥ 30 mm ≥ 30 mm
[1-3/16 in] [1-3/16 in]
0.9
0.9
0.9
1.2
2.1
2.1
2.1
2.1
2.7
3.7
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