Hydraulic Characteristic; Expansion Tank - Biasi RinNOVA 24S User Manual And Installation Instructions

4.7 Hydraulic characteristic

The hydraulic characteristic represents the
pressure (head) available in the heating sys-
tem based on the flow rate.
0,6
0,5
0,4
0,3
0,2
0,1
0,0
0 200 400
Figure 4.4
0,6
0,5
0,4
0,3
0,2
0,1
0,0
0 200 400 600
Figure 4.5
The loss of load for the boiler has already been
subtracted.
Flow rate with the thermostatic cocks
closed
The boiler has an automatic by-pass, which
protects the primary exchanger.
If the circulation of water in the heating system
decreases too much or totally stops due to the
closure of thermostatic valves or circuit cocks,
the by-pass guarantees a minimum circulation
of water inside the primary exchanger.
The by-pass is calibrated for a differential pres-
sure of approx. 0.3 - 0.4 bar.
TECHNICAL SPECIFICATIONS
24-28 kW
600 800 1000 12001250
l/h
32 kW
800 1000 1200 1400
l/h

4.8 Expansion tank

The difference in height between the safety
valve and the highest point in the system can
be max. 10 metres.
If differences are greater, increase the preload
pressure of the expansion tank and the cold
system by 0.1 bar for each 1 metre increase.
Total capacity
Preload pressure
Useful capacity
Maximum system
content *
Figure 4.6
* In conditions of:
• Average max. temperature of the system
85°C
• Initial temperature when filling the system
10°C.
For systems with contents that ex-
ceed the maximum system content
(indicated in the table), a supple-
mentary expansion tank must be
installed.
l 7.0
kPa 100
bar 1.0
l 3.5
l 109
- 31 -