Function; Hot Water - Würth IVT LATENTO XXL 500 Notice De Montage

5. Function

Unpressurised solar stratified storage tank:
The storage water in the LATENTO XXL is only used for heat
absorption. The heat is fed in and taken via heat exchangers.
Hence the storage water does not have any contact to the heat-
ing or DHW system. Thereby problems such as furing up and
sludge accumulation in the storage tank and legionella growth
in the DHW heat exchanger is prevented.
Solar yield:
Primaly, free solar energy, which is utilized for DHW heating
and (optionally) to back up heating is stored in the LATENTO
XXL. The solar heat is fed in the LATENTO XXL via the solar
heat exchanger. This happens as soon as the temperature
in the collector is higher than the temperature in the lower
Illustrations similar: XXL 500
storage tank region and as long as the LATENTO XXL is fully
heated to maximum temperature. The maximum temperature is stored in the con-
trol system which is normally preset to 80 °C. By this, a temperature of approx.
85 °C is reached in the upper region (cf. Picture of
upper storage tank region for hot water supply).
DHW + solar yield:
First of all, the cold water in the DHW heat exchanger will flow through the lower
storage tank region. Thereby the region of solar feed-in is cooled and the DHW
preheated at the same time. By this, relatively low temperature levels can be uti-
lized too. At the same time, the extraction volume for the hot water is increased.
The solar yield increases through cooling of the lower storage tank region because
a larger temperature spreading between feed and return increases the perfor-
mance of the solar heat exchanger. So the LATENTO XXL can be charged faster
and use solar heat already at low temperatures.

Hot water:

The hot water is heated following the continous flow heater principle. Thereby
the hot water is always generated whenever required. The advantage: The water
is fresh at all times, and legionellae have no chance of growing. What´s more,
the stainless steel heat exchanger guarantees perfect drinking water quality and
corrosion resistance.
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