Hitachi RWM-(H)FSN3E Technical Catalogue page 49

2 Features and benefits
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Space heating priority mode
The Domestic Hot Water (DHW) operation has priority over all other operation modes unless otherwise noted.
It should be taken into account the following considerations:
• When DHW requires the heat pump operation, no other modes can require heat pump operation.
• If DHW does not require heat pump operation, it is stopped or works with heater only, there is no restriction on the
other operation modes.
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DHW Anti-Legionella protection (Optional function)
In order to help protect against Legionella into the DHW system, it is available a specific setting which will raise up the DHW
periodically (by the DHW tank electric heater or by a boiler) over the normal DHW tank temperature setting.
The following parameters should be configured for the Anti-Legionella function:
Anti-Legionella
temperature
DHW setting
temperature
N O T E
For more details about the Anti-Legionella optional function protection, please refer to the Service Manual
(SMXX0070).
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Maximum water set-point by the installer
The installer can set a maximum water tank temperature in order to avoid excessively hot water in the DHWT.
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Two different modes for DHW
The DHW operation will be performed by two different modes:
• Standard mode: The DHWT will start heating when the water tank temperature is low enough for heat pump to be
started. In this mode, the DHW is always heated by the heat pump.
• High demand mode: The DHWT will start heating if the difference between the maximum water set point temperature
and the actual DHW temperature is bigger than a predetermined value. Only the DHWT electric heater will start hea-
ting unless DHW temperature goes below the heat pump starting temperature.
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DHWT heating by timer
It is available a DHWT timer program provided in the unit (by the LCD user's interface) in order to enable/disable de DHW
operation. It can be programmed each day of the week.
N O T E
For more information, please refer to the Service Manual (SMXX0070).
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Combinability with solar panel
As it has been explained in section
solar combination will enable to heat up the DHW by means of the sun. The solar combination is designed to transfer the
heat from the solar panels (sun radiation) to the heat exchanger of DHW tank.
N O T E
For more information, please refer to the section Installation
49
TCGB0070 rev.3 - 04/2012
Selection benefits, the air to water heat pump can be combined with solar panel. The
• Operation interval: Day(s) of the week at which
the domestic water should be heated.
• Status: Defines whether the disinfection
function is turned ON or OFF.
• Start time: Time of the day at which the DHW
should be heated.
• Anti-Legionella temperature: High water tempe-
rature to be reached.
• Interval: Time period during the Anti-Legionella
temperature remains constant.
Time
configurations.
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