Hisense Hi-Therma-Serie Bedienungsanleitung Seite 34

The storage capacity of the DHW tank depends on the daily
water demand and the combination method. The daily water
demand is estimated with the following calculation formula
for consumption:
D (T)= D (60 °C) x (60-T
i i
Where:
D Water demand at T temperature
(T):
i
D Domestic hot water demand at 60 °C
(60°C):
i
T: Temperature of the DHW tank
T Temperature of the inlet cold water
:
i
- Calculation of D (60 °C):
i
The standard consumption, expressed in daily liters per
person and determined by technical installation regulations
of each country, is used to calculate the domestic hot water
demand at 60 °C, D (60 °C). This quantity is then multiplied
i
by the expected number of users of the installation. In the
following example, the domestic hot water demand at 60 °C
has been considered as 30 liters per person, in a detached
house with 4 residents.
- Calculation of T:
The temperature of the DHW tank refers to the temperature
of the accumulated water inside the tank, prior to operation.
This temperature is usually between 45 °C and 65 °C. It has
been considered as 45 °C in this example.
- Calculation of Ti:
The temperature of the inlet cold water refers to the
temperature of the water being supplied to the tank. Since
this temperature is usually between 10 °C and 15 °C, it has
been considered as 12 °C in this example.
- Example:
Di(T)= 30 x 4 x (60-12 / 45-12) = 174.5 liters/day
174.5 x 2(*) = 349 liters/day approximate demand of hot
water
(*) It is recommended to multiply the calculated consumption by two,
in case that the installation is in a detached house. This is done to
ensure a steady supply of hot water. In the case of a multifamily
installation, it is not necessary to increase the forecast of hot water
demand, given the lower simultaneity factor.
/ T-T )
i i
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SPACE HEATING/COOLING AND DHW