Panasonic Aquarea WH-SDC16H6E5 - Heating Water Quality; Use of Buffer Tanks

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Aquarea air-to-water heat pumps - Planning and installation manual - 02/2022
Planning
5
i
Note
The calculation of the expansion vessel is done according to EN 12828 “Heating systems in
buildings – Design for water-based heating systems”. The design programs for expansion vessels,
which are provided by the respective manufactuerer, can be used to design the expansion vessel
based on the local requirements. These programs can also determine the required initial pressures
to be set on the expansion vessel.
5.3.6 Heating water quality
ATTENTION
Danger of damage to pipes due to corrosion
Ingress of oxygen into open water systems can cause excessive corrosion of the pipes and the
subsequent problems in operation.
► Install Aquarea heat pumps only as closed systems without direct contact of the heating
water to the ambient air.
To avoid damage to the heating system and to the heat pump, use water that complies with
the currently valid version of the European Water Quality Directive 98/83/EC and respect any
corresponding national requirements, which are applicable. It is recommended to avoid the use of
groundwater, such as spring water or well water, the use of tap water, when salt or other impurities
are contained, and the use of acidic water. Furthermore, the heating system is to be thoroughly
purged before lling with heating water.
5.3.7 Use of bu󰀨er tanks
Bu󰀨er tanks can full three functions in the context of heat pumps:
● Bridging electricity shutdown times imposed by the electric utility company
● Hydraulic separation of heat pump circuit and heat transfer system
● Extension of the heat pump run time to avoid frequent on/o󰀨 switching (cycling), which
reduces the system e󰀩ciency
Thanks to inverter technology, system performance can be controlled by Aquarea heat pumps
based on the current heat demand. The heat pumps can therefore be operated even without a
bu󰀨er tank, to achieve higher e󰀩ciency and save on space. To bridge electricity shutdown times
imposed by the electric utility company, heat transfer systems with greater tank capacity such as
under-oor heating can provide adequate intermediate storage.