Product Overview

Installation
The differential by-pass valve can be fitted in any position, respecting
the flow direction indicated by the arrow on the valve body.
In systems with a traditional boiler it is normally fitted between the
system flow and return ends, which allows the control of the pressure
and the passage of a minimum flow through the heat generator.
In systems with a condensation boiler, it is preferable to fit the
by-pass directly between the upstream and downstream sections
of the pump, as this allows a higher ΔT in the circuit, with lower
return temperatures and therefore better operation of the system.
In the event of high by-pass flow rate levels, it is recommended to
fit the valve between the flow and return ends of each column,
rather than fitting a number of valves in parallel at the central boiler.
Δp (m w.g.)
0
120,5 1,5
1
2
3
4
5
6
7
8
Flow rate (m
3
/h)
(kP
a
0
10
20
30
40
50
60
70
80
10123456789
(kPa)
0
10
20
30
40
50
60
70
80
0
1
2
3
4
5
6
7
8
Δp (m w.g.)
Flow rate (m
3
/h)
Hydraulic characteristics
code 519700 (1 1/4”)code 519500 (3/4”)
Setting
positions
1
2
3
4
5
6
➧
Setting
positions
1
2
3
4
5
6
➧
Δp (m w.g.)
0
10,5 1,5
10
20
30
40
50
60
Flow rate (m
3
/h)
(kPa)
0
100
200
300
400
500
600
code 519504 (3/4”)
Setting
positions
1
2
3
4
➧
Application diagrams
RT
RT
Shut-off valve
Pump
Room thermostat
Check valve
Insulated manifold
Two way zone valve
Autoflow
Thermostatic valve
Automatic air vent
RT
Small-medium size system
by-pass in central plant
mH
2
O
1 2 3 4 5 6