Technical data

FROST PROTECTION
The frost protection function is active even when the heat pump
is OFF.
DOMESTIC HOT WATER FROST PROTECTION STOR-
AGE
The domestic hot water frost protection function is only active if
an auxiliary resource is installed for the domestic hot water stor-
age tank.
The additional heater is activated if the water temperature,
measured by sensor BT8, is less than +5°C, and is deactivated
at +8°C.
PRIMARY CIRCUIT FROST PROTECTION SYSTEM
The frost protection function is implemented by starting the sys-
tem pump and, where featured, the electric heater outside of
the unit when the water temperature water (measured by the
heat exchanger outlet probe) is less than 4.5°C, and switching
the same devices off when the water temperature reaches
+7°C.
SECONDARY CIRCUIT FROST PROTECTION SYS-
TEM
The pumps on the system’s secondary circuit are activated
together with the primary pump, according to the criterion
described in the previous paragraph.
FROST PROTECTION BASED ON OUTSIDE AIR TEM-
PERATURE
The system pump is activated according to the outside air tem-
perature to prevent ice forming in the pipes.
The pump is activated if the outside air temperature is less than
4°C and deactivated when it rises back over 5°C.
FROST PROTECTION BASED ON INSIDE AIR TEM-
PERATURE
The heat pump and/or supplementary heat sources (outlet
heater or boiler) are activated if the inside temperature falls
below 14°C, to prevent the pipes inside the home from freezing.
ALARM SIGNALS
Correct unit operation and any alarms are displayed on the
room thermostat, the latter by the symbol.
The diagnostics functions include complete alarm management,
with an alarm log (via service keypad) for more detailed analy-
sis of unit behaviour.
i-KI(R) MTD
HFC 410Ai-KI(R)_MTD_0031_201110_EN
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