GB
24
The following sample calculation can be helpful for dimensioning the buffer
tank:
The following assumptions have been made in this regard:
Senso M H
2
O
Piko H
2
O
• Size of the buffer tank: 750 l
(approx. 750 kg water)
• Water temperature in the buffer
tank at the beginning: 30°C
• Water temperature in the buffer
tank at the end: 60°C
• Temperature differential 30°C
(corresponds to 30 K)
• Water is not taken from the tank
during heating by the Senso M
H
2
O!
• Size of the buffer tank: 500 l
(approx. 500 kg water)
• Water temperature in the buffer
tank at the beginning: 40°C
• Water temperature in the buffer
tank at the end: 70°C
• Temperature differential 30°C
(corresponds to 30 K)
• Water is not taken from the tank
during heating by the Piko H
2
O!
Q = cp×m×
∆
t
Q = 4,187 kJ × 750kg×30K
kg×K
Q = 94207 kJ
Q = cp×m×
∆
t
Q = 4,187 kJ × 500kg×30K
kg×K
Q = 62805 kJ
This means: To heat up 750 litres
of water in a buffer tank, from an
assumed 30°C to 60°C, a theore-
tical heat quantity of 94207 kJ is
required (losses or heat withdra-
wals in the system have not been
taken into account). This heat
quantity corresponds to approx.
26.2 kWh.
This means: To heat up 500 litres
of water in a buffer tank, from an
assumed 40°C to 70°C, a theore-
tical heat quantity of 62805 kJ is
required (losses or heat withdrawals
in the system have not been taken
into account). This heat quantity
corresponds to approx. 17.5 kWh.
ϑ
E
F
G
H
K
L
M
N
P
O
Q
R
S
I
J
B
T
C
D
A
A =
temperature sensor for thermal discharge safety valve
B =
temperature sensor for thermostatic switch ½'' IG
C =
return ¾'' IG
D =
flow ¾'' IG
E =
safety valve 3 bar
F =
bleeding
G = t
hermostatic switch - pump
H =
return riser
I =
connection for heating system
J =
buffer reservoir
K =
return flow temperature boost
L =
circulation pump
M =
filling and draining fitting
N =
diaphragm expansion tank
O =
thermal discharge safety device
P =
free discharge in e.g. sewer network
Q =
"discharge" safety heat exchanger ½'' IG
R =
"inlet" safety heat exchanger ½'' IG
S =
bleeding
3
/
8
¨
T =
thermal discharge safety device
