Automatic Protection Functions - Vaillant geoTHERM VWS 220/2 Instrucciones De Operación

that of the brine flowing through the evaporator. The cool-
ant can thus take up more thermal energy in the evapora-
tor, turning into vapour in the process and flowing to the
compressor. The cycle starts again.
The evaporator, the brine pump/well water pump, pipes in
the brine/well water circuit and parts of the coolant circuit
are cold-insulated inside the water pump, meaning that no
condensation can accumulate. If condensation should ever
accumulate in small amounts, this will be collected by the
condensate pan. The condensate pan is located on the
inside, in the lower part of the heat pump. As a result of the
heat generated inside the heat pump, the condensation in
the condensate pan evaporates. Small amounts of the accu-
mulating condensation can be drained off under the heat
pump. In small amounts, accumulating condensation should
thus not
be seen as a fault in the heat pump.
The geoTHERM heat pumps can be equipped with external
passive cooling in order to provide for comfortable, cool
room temperatures in your living rooms at high outside
temperatures during the summer operation. For this pur-
pose, additional components are required in the heat pump
hydraulics. An auxiliary cooling heat exchanger, an addi-
tional mixer valve and an auxiliary diverter valve.
In the case of Vaillant heat pumps with cooling function, the
principle of „passive" cooling is applied, in which thermal
energy is transported via underfloor heating from the
rooms to the ground without compressor operation and
therefore without coolant circuit operation. The heating
water, which when supplied is colder than the room temper-
ature, absorbs thermal energy from the rooms and is
pumped via the CH pump into the cooling heat exchanger.
The brine pump also conveys the colder brine from the
ground into the heat exchanger of the brine circuit, which is
operated in the counter flow principle. In the process, the
warmer heating return emits thermal energy to the colder
brine circuit, so that the brine which is heated to some
degree is guided again
to the floor. The annealed heating flow circulates again
through the circuit of the underfloor heating, where the
water can reabsorb thermal energy from the surroundings.
The cycle starts again.
Your heat pump can be set up in such a way that during
installation, certain heater circuits (e. g. bath) are excluded
from the cooling function, whereby so-called stop valves
are installed and controlled by the heat pump.
For more information, consult your heating engineer.

3.2.2 Automatic protection functions

In automatic mode, the heat pump is equipped with a
number of automatic protection functions in order to guar-
antee fault-free operation:
Operating instructions geoTHERM 0020051578_03
Unit function and design
Frost protection functions
The heat pump features two frost protection functions. In
standard operation, the heat pump provides regulated frost
protection for the system. If the heat pump shuts down for
a prolonged period of time due to a fault, the electric auxil-
iary heater provides emergency frost protection and, if nec-
essary, enables emergency operation.
Regulated frost protection - heating
This function ensures that your heating installation is pro-
tected from frost in all operation modes.
If the outside temperature falls below a value of 3 °C, the
night set back temp. is automatically programmed for each
heater circuit.
Regulated frost protection - domestic hot water
cylinder
This function prevents the connected domestic hot water
cylinder(s) from freezing.
The function is automatically enabled when the actual tem-
perature of the domestic hot water cylinder drops below
10°C. The cylinder(s) is (are) then heated to 15 °C. This func-
tion is also active in the „Off" and „Auto" operation modes,
regardless of the time programmes.
Emergency frost protection function
In the event of a heat pump failure, the emergency frost
protection function automatically enables the optional
external auxiliary heater in accordance with the setting for
the heating mode and/or hot water handling.
Testing the external sensors
This function uses the control diagram entered during com-
missioning to continuously check whether the sensors
stored within it are installed and fully functioning.
Protection against loss of heating water
This function continuously monitors the pressure of the
heating water in order to prevent a possible loss of heating
water. An analog pressure sensor shuts down the heat
pump when the water pressure drops below 0.5 bar. It
switches the heat pump on again when the water pressure
rises above 0.7 bar.
Automatic pump spin and valve blocking protec-
tion
This function prevents a circulation pump and all diverter
valves from seizing. To do this, every day, the pump and the
valves that have not been operated for 24h are switched on
in succession for around 20 seconds.
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