Mitsubishi Electric PURY-WP-YJM-A, Data Book

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3. Piping Design
4 - 29 SYSTEM DESIGN
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3-2-3. Connecting water pipework
Please observe the following precautions during installation.
3-2-3-1 Important notes on water pipework installation
Example of heat source unit installation (using left piping)
• The design pressure of the HBC water system is 0.6MPa.
• Use water pipe-work with a design pressure of at least 1.0MPa.
• When performing a water leak check, please do not allow the water pressure to go above 0.3MPa.
• 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 must 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 fittings, 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 the pipe work. If the system is stopped for an extended period
during low ambient conditions, 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.
• Hold the pipe on the unit side in place with a spanner when installing the pipes or strainer. Tighten screws to a torque of 40 N·m.
• If there is a risk of freezing, take precautions to prevent this happening.
• When connecting the HBC unit water piping and on site water piping, apply liquid sealing material for water piping over the
sealing tape before connection.
• Please use copper or plastic pipes for the water circuit. Do not use steel or stainless steel pipework. Furthermore, when using
copper pipe-work, use a non-oxidative brazing method. Oxidation of the pipe-work will reduce the pump life.
Expansion tank
Manual Air purge valve
Shutoff valve
Shutoff valve
Drain pipe
Refrigerant pipes
Strainer
Water inlet
Pressure reducing valve
HBC controller sample installation
• The HBC system must be serviced at least once a year.