4

Installation Guide 

ASV‑PV (DN 15‑50)

SMT/SI 

VI.A1.I7.7O 

Heating Solutions

ENGLISH

Automatic balancing valves ASV‑PV is used 
together with shut‑off and measuring valve 
ASV‑M to control the differential pressure 
in risers where the radiator valves have 
presetting facilities. ASV‑PV is also used 
together with adjustment valve ASV‑I to 
control the differential pressure and flow 
in risers where the radiator valves have no 
presetting facilities (P/Q control), fig. ❶.
ASV‑PV maintains constant differential 
pressure across the riser.
Max. working pressure  ...........................16 bar
Differential pressure across valve:
DN 15 ‑ 40  ...........................................10‑150 kPa

DN 50  .................................................. 10‑250 kPa 

Max. flow temperature............................120 °C

Valve size

Internal 

thread

External 

thread

DN 15

Rp ½

G ¾ A

DN 20

Rp ¾

G 1 A

DN 25

Rp 1

G 1¼ A

DN 32

Rp 1¼

G 1½ A

DN 40

Rp 1½

G 1¾ A

DN 50

‑

G 2½

Impulse line: G 1⁄16

Installation 

ASV‑PV must be installed in the return 
pipe. The flow must be in the direction of 
the arrow on the valve body fig. ❸.
It is recommended that an FV filter be 
installed in the system supply pipe. The 
impulse tube must be fitted on the flow 
pipe, e.g. via an ASV‑I or an ASV‑M valve.
The tube must be flushed through before 
being fitted on the + connection of the 
ASV‑PV automatic balancing valves fig. ❷.
ASV‑PV must in addition be installed as 
determined by installation conditions. 
When the system has been in use for 
some time, the connections with external 
threads should be tightened once again to 
minimize the risk for leakage.

Shut‑off

Turning the ASV‑PV knob fully clockwise 
will shut‑off the riser fig. ❷ ①.

Pressure testing

Max. test pressure  ....................................25 bar

Notes:
When pressure testing you must secure that 
both sides of the membrane have the same 
static pressure. That means the impulse 
tube must be connected and any needle 
valves must be open. If ASV‑PV is installed 
in combination with ASV‑M both valves can 
be open or closed (both valves must be in 

the same position!). If ASV‑PV is installed in 
combination with ASV‑I both valves must 
be open. During this operation (closing or 
opening the valves) please make sure that 
there is never lower pressure on upper side of 
the membrane.
If ASV‑ PV is installed in combination with 
ASV‑I do not drain main pipes while leaving 
risers under pressure / filled with water. Doing 
so ASV‑PV membrane would have lower 
pressure on upper side which might damage 
the membrane.

If this instructions are ignored, the membrane 
of the automatic balancing valve might be 
damaged.

Setting/adjustment 

The ASV‑PV valves are sold in four different 
∆p setting ranges. The valves are factory–
set to a defined value as described on 
Factory presseting table on fig. ❾. Use 
the following procedure to set the desired 
differential presure: the setting on ASV‑PV 
can be changed by turning the setting 
spindle fig. ❷②. 
Turning the spindle clockwise increases 
the setting; turning it counter clockwise 
reduces the setting.

If the setting is not known, turn the spindle 
fully clockwise. With this the setting on 
ASV‑PV is at maximum value within setting 
range. Now turn the spindle a number of 
times (n) as described in fig. ❾ until the 
required differential pressure setting is 
obtained. 

Note: 
Do not turn the spindle more than 20 turns as 
it will become disengaged.
The cock (closed, fig. ❹–① ‑ open, 
fig. ❹–②) can be used for water tapping 
and filling.

Starting

You can fill the system with the drain‑cock 
on ASV‑PV. The system shall be ventilated 
at the highest point. During system start 
– opening the shut‑off on ASV‑PV and 
partner valve ‑ please secure that there 
is the same static pressure on both sides 
or higher pressure on upper side of the 
membrane (+ connection, Fig.❷). If filling 
is done by opening ASV‑PV and partner 
valve, please make sure there is a pressure 
on the upper side of the membrane by 
opening partner valve first before ASV‑PV 
is opened.

Notes! 

a)  ASV‑PV used with ASV‑M (Fig. ❻): 

if this procedure is not followed, the 
membrane of ASV‑PV might be damaged.

b)  ASV‑PV used with ASV/I (Fig. ❼): 

If this procedure is not followed, ASV‑PV 
may become locked in closed position 
even if the valve is fully opened.

c)  Both ASV‑PV and ASV‑M/I should be 

always fully opened if used together with 
dedicated shut‑off valves (Fig. ❽).

Fault location

Check the following if the riser valve does 
not function correctly:
1.  Is the flow direction through the valve 

correct?

2.  Is the impulse tube fitted correctly and 

are any needle valves open?

3.  Is the valve shut‑off open?

Insulation (DN 15 ‑ 40)

The styropor packaging in which the valve 
is supplied can be used as an insulation 
jacket for temperatures up to 80 °C.