Mitsubishi Electric City Multi PURY-M200YNW-A1 Data Book page 84

11. PIPING DESIGN
11. Please refer to the figure below when connecting the water supply.
HBC controller
12. Use formula 0.1 ≤ 0.01 + 0.01 × A ≤ 0.16 for the supply pressure range to be used.
(A: Head pressure (m) between the HBC and the highest indoor unit)
If the supply pressure is greater than 0.16 MPa, use a pressure reducing valve to keep the pressure within the range.
If the head pressure is unknown, set it to 0.16 MPa.
13. Install a shut off valve and strainer in a place that is easy to operate and makes maintenance work easy.
14. Apply insulation to the indoor unit pipework, strainer, shut off valve, and pressure reducing valve.
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. For the brine selection, refer to 8-5. "Correction by antifreeze solution concentration".
11-2-3-3 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 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
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.
MEES18K068
Shutoff valve
Pressure gauge
(field supply)
(field supply) Check valve
Water
(field supply)
pipe
Strainer
(field supply)
Pressure reducing
valve (field supply)
R2-Series
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