Hydraulic Characteristics; Expansion Vessel - Biasi RINNOVA COND 24S User Manual And Installation Instructions

4.7 Hydraulic characteristics

The hydraulic characteristics represent the
pressure (head) available in the heating
system based on the flow rate.
Model M275V.2024 SM
Pressure (bar)
0,55
0,50
0,45
0,40
0,35
0,30
0,25
0,20
0,15
0,10
0,05
0,00
0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500
Figure 4.4
Model M275V.2428 SM - M275V.2832 SM
Pressure (bar)
0,55
0,50
0,45
0,40
0,35
0,30
0,25
0,20
0,15
0,10
0,05
0,00
0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1450 1500
Figure 4.5
The load loss 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 condensate exchanger.
If the circulation of water in the heating sys-
tem decreases too much or totally stops
due to the closure of thermostatic valves or
circuit cocks, the by-pass guarantees a min-
imum circulation of water inside the primary
TECHNICAL SPECIFICATIONS
Flow rate (l/h)
Flow rate (l/h)
condensate exchanger.
The by-pass is calibrated for a differential
pressure of approx. 0.3-0.4 bar.

4.8 Expansion vessel

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 pre-
load pressure of the expansion tank and the
cold system by 0.1 bar for each 1 metre in-
crease.
Total capacity
Pre-load pressure
Useful capacity
Maximum system content *
Figure 4.6
* In conditions of:
• Max. average system temperature of
85°C
• Initial temperature when filling the system
10°C.
For systems with contents that
exceed the maximum system
content (indicated in the table),
a supplementary
tank must be installed.
l 7.0
kPa 100
bar 1.0
l 3.5
l 109
expansion
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