- 24 -
INST
ALLA
TION
TECHNICAL INFORMATION
4.5
Hydraulic specifications
The hydraulic specifications in Fig. 4.3 rep
-
resent the pressure (available head for the
central heating system) as a function of the
flow rate.
The load loss due to the boiler has already
been subtracted.
Fig. 4.3
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0
200
400
600
800 1000 1200 1400
0
10
20
30
40
kPa bar
l/h
60
50
Output with thermostat cocks shut off
The boiler is equipped with an automatic by-
pass valve (
38
on page 17), which protects
the condensing primary exchanger.
In case of excessive reduction or total
blockage of water circulation in the cen
-
tral heating system owing to closure of the
thermostatic valves or system component
cocks, the by-pass valve ensures a mini
-
mum flow of water through the primary heat
exchanger.
4.6
Expansion vessel
Note: this boiler is designed for operation
only in a sealed central heating system
The height difference between the pressure
relief valve and the highest point in the sys
-
tem may be 10m at most.
For greater differences, increase the pre-
load pressure in the expansion vessel and
the system, when cold, by 0.1 bar for each
additional 1 m.
Fig. 4.4
Capacity
l
8,0
Pre-load pressure
kPa
100
bar
1,0
Maximum volume of water in the
system *
l
124
* Where conditions are:
•
Average maximum temperature of the sys
-
tem is 85 °C
•
Initial temperature when filling up the sys
-
tem is 10 °C
For systems with volumes great-
er than 124 l, an additional ex
-
pansion vessel must be provid-
ed.
Summary of Contents for RIVA PLUS HE 24S ERP
Page 55: ......
