Hitachi YUTAKI RWM-2R1E Installation & Operation Manual page 272

YUTAKI CASCADE CONTROLLER ATW-YCC-(01-02)
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Solar combination - Total control
ΔT connection:
• Allows to specify a difference
temperature between tank and Panel
temperature to allow solar operation.
Solar operation is allowed in case Panel
temperature is "ΔT connection" ºC above
tank temperature.
ΔT disconnection:
• Allows to specify a difference
temperature between tank and Panel
temperature to stop solar operation.
Solar operation is not allowed in case
Panel temperature is "ΔT connection"ºC
below tank temperature
Panel antifreeze temperature:
• Minimum Solar panel temperature at
which Solar Pump is switched ON in
order to protect system against frost
formation at pipes due to low ambient
temperature.
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Boiler combination
Minimum ON time:
• Time that must pass before stop
boiler after being switched ON
Minimum OFF time:
• Time that must pass before start
boiler after being switched OFF
Wait time for DHW:
• Delay time to start Boiler for DHW
in case all conditions allow Boiler
to start after HP has been started
for DHW.
258 PMML0575 rev.2 - 03/2022
DHW maximum time:
• Maximum time YUTAKI allows to heat tank by means
Solar. At the end of this time Solar pump is stopped
regardless temperature conditions at Solar Panel.
DHW minimum time:
• Minimum Time solar operation cannot be performed
once it has been stopped due to DHW Maximum Time
or due to low temperature at solar panel.
DHWT maximum storage temperature:
• Maximum DHW temperature that allows Solar
operation.
Panel minimum temperature:
• Minimum temperature of the solar Panel to allow Solar
operation
Panel overheat temperature:
• Maximum panel operation temperature at which
Solar Pump is set to off in case Panel sensor reads a
temperature above this value in order to protect system.
• In case Solar pump is stopped due to Panel Overheat
temperature, YUTAKI unit sets Solar overheat output
to high state in case of configured in
inputs, outputs and sensors"
Bivalent point:
• Boiler is allowed to operate in case ambient temperature is
below this value
Combination mode:
• Serial: Boiler operates in series with the heat-pump. The
boiler provides additional peak load capacity and works
together with the HP
• Parallel: Boiler operates in parallel with the heat pump.
The boiler provides the full heating requirements. In case
Boiler is ON, HP is not allowed to operate
Supply setting offset:
• Setting offset for Boiler. Higher values imply earlier
stoppage of Boiler and vice versa.
Waiting time:
• Delay time to start Boiler in case all conditions allow Boiler
to start after HP has been started for Space Heating
DHW by boiler:
• Control to allow heat DHW by means Boiler
"10.6.2.9 Setup of