Mitsubishi Electric CITY MULTI PLFY-WL-NEMU-E Serie Manual De Instalación página 7

4. Connecting water pipes
Please observe the following precautions during installation.
4.1. Important notes on water pipework installation
• The water pressure resistance of the water pipes in the heat source unit is 1.0MPa
[145psi].
• Please connect the water pipework of each indoor unit to the connect 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 fl owing water through the pipe,
vent any excess air.
• Secure the pipes with metal fi tting, 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 pipe-work installed incorrectly
(inlet connected to outlet and vice versa).
• This unit doesn't include a heater to prevent freezing within tubes. If the water fl ow
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 fi lled with putty.
• Install water pipe so that the water fl ow rate will be maintained.
B A
Fig. 4-1
• 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 proofi ng 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.
4.2. Water pipe installation for connection with HBC
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 controller.
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 controller control box (for
identifi cation purposes), and HBC controller 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 insuffi cient, there is a possibility of condensation, etc. Pay
special attention to insulation work in the ceiling plenum.
(Fig. 4-2)
A A Locally procured pipe insulation
B Tighten this location with a band (procured locally)
C Do not separate from the opening
A Water pipe: Outlet
D Wrap overlap: 40 mm, 1-9/16 inch or more
B Water pipe: Inlet
E Insulation material (procured locally)
F Unit side insulation material
G Depending on the selected joint, there may be a gap between the unit side pipe cover and
the joint.
If there is a gap, fi ll in the gap with the pipe covers prepared on-site.
• Insulation materials for the pipes to be added on site must meet the following
specifi cations:
• This specifi cation is based on copper for water piping. When using plastic pipework,
choose a thickness based on the plastic pipe performance.
• Installation of pipes in a high-temperature high-humidity environment, such as the
top fl oor of a building, may require the use of insulation materials thicker than the
ones specifi ed in the chart above.
• When certain specifi cations presented by the client must be met, ensure that they
also meet the specifi cations on the chart above.
4.Expansion vessel
Install an expansion vessel to accommodate expanded water. (circuit protection valve
set pressure: 600 kPa)
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.
• The circulation pump head pressure is 0.24 MPa.
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.
Unit model
PLFY-WL06NEMU-E
PLFY-WL08NEMU-E
PLFY-WL12NEMU-E
PLFY-WL15NEMU-E
PLFY-WL18NEMU-E
PLFY-WL24NEMU-E
PLFY-WL30NEMU-E
PLFY-WL36NEMU-E
PLFY-WL48NEMU-E
unit
B
A
D
Fig. 4-2
HBC controller-indoor unit 20 mm, 25/32 inch or more
Water out
Inner diameter
≥ 20 mm, 25/32 inch
Inner diameter
≥ 30 mm, 1-3/16 inch
C
F
E
G
Pipe size
Water
volume (ℓ)
Water return
1.0
1.0
Inner diameter
1.8
≥ 20 mm, 25/32 inch
1.8
1.8
2.1
2.1
Inner diameter
≥ 30 mm, 1-3/16 inch
2.2
3.1
5
en