Summary Of Operations; Domestic Hot Water Production - Hitachi YUTAKI Serie Installations- Und Betriebshandbuch

GENERAL INFORMATION
YUTAKI S80
The YUTAKI S80 is a standalone indoor unit that generates hot water up to 80ºC; the hottest water temperature in the domestic
heating market using renewable energy.
The extra innovation in the YUTAKI S80 lies in that it has two compressors, working in a smart cascade system, with two refrigerant
cycles (R-410A and R-134a). To maximize seasonal efficiency, the second refrigerant cycle is only operated as a booster, when very
high water temperature is required - the rest of the time, only one cycle is used.
The YUTAKI S80 is ideal for existing properties, in particular older installations where high water supply temperatures may be
required to keep the house warm – as well as for new buildings. It is designed for the replacement of boilers, offering heating and
sanitary hot water all year round, without boiler back-up.
Two different models have been designed for different purposes: one model for space heating only and the other one for space
heating as well as for DHW operation. For DHW operation (optional), HITACHI offers two specific YUTAKI S80 DHW tanks
(DHWS200S-2.7H2E and DHWS260S-2.7H2E) which may be placed on top of the indoor unit or besides it, as an integrated unit to
provide high-temperature domestic hot water enjoying the benefits of the high efficiency of the heat pump.
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Monobloc system - YUTAKI M
YUTAKI M is a monobloc air to water heat pump system, composed by only an special outdoor unit, which carries out the function of
an air-to-water heat pump. This results in an excellent solution when installation space available is limited.
YUTAKI M is designed to be installed outdoors, in any kind of dwelling (house, apartment, villa,...), whether in a new construction or
in an existing building. Installation work is greatly simplified thanks to the lack of refrigerant piping connections.

1.1.2.2 Summary of operations

Space heating
YUTAKI units are factory-supplied ready for space heating operation. Different heating installation configurations can be selected
providing a comfortable atmosphere all year long even in the coldest climates:
• Mono-valent system
The air to water heat pump is sized to provide 100% of the heating requirements on the coldest day the year.
• Mono-energy system
This is the most popular configuration. The air to water heat pump is sized to provide 80% of the heating requirements on the
coldest days of the year. An auxiliary electric heater is used to provide the additional heating required on cold days. This option
usually results in an ideal balance between installation costs and future energy consumption, as proven by its popularity in colder
climates than ours, such as Sweden and Norway.
• Alternating Bi-valent system
For installations with an existing heating system by boiler, and when is needed to heat the supplied water temperature to the
circuit up to high temperatures (80ºC), the boiler can be configured to alternate with the air to water heat pump.
Selecting the different configuration types it is possible to adapt the system to all customer requirements, providing a wide
application range from the simplest configuration to complete configuration: Radiator, heating floor or both (2nd temperature area).

Domestic hot water production

YUTAKI models also give the option of domestic hot water production, allowing the user to benefit from the heat pump's high
efficiency and achieve domestic hot water.
This is made possible by a domestic hot water tank. In case of YUTAKI S COMBI, the domestic hot water tank is built in the indoor
unit. In YUTAKI S80, a specific DHW tank is designed for combination with the indoor unit. For YUTAKI S and YUTAKI M, the
HITACHI accessory "DHWT-(200/300)S-3.0H2E" can be used for the production of DHW.
An electric heater is incorporated inside the tank in order to allow an immediate heating of the domestic hot water in accordance with
the user's needs.
2 PMML0335A rev.1 - 04/2016