Area of use

The differential pressure valves PVM is used to distribute the flow within different areas in heating and cooling systems.
The differential pressure valves PVM consists of a differential pressure valve (PV) and a balancing valve (STV).
PVM maintains the differential pressure across a circuit, such as a stem, which supplies radiators or to secure differential pressure over a control valve so that good authority is achieved for modulating regulation.
The differential pressure held constant, can be adjusted to achieve the prescribed flow.
At increased available pressure, the differential pressure valve closes and at reduced pressure, the differential pressure valve opens.
The PVM package also includes a shut-off valve so that the circuitry return and return pipes can be closed.

Description

Measuring
The PVM is equipped with four measuring sockets for measuring the pressure drop of the valves, available pressure and differential pressure across the load. See the section for troubleshooting.
The cover is disassembled on the valve’s outlet socket, then the differential pressure can be measured.
To measure the differential pressure across the STV valve, open the ball valve on the measuring outlet.

Mounting
The STV and PV valve have flow direction marked on the valve body.
The PV valve is mounted on the return and STV at the inlet.
The capillary tube is mounted between the valves and aired before connecting.
NOTE! The capillary tube must not be cut.

Technical data

Max. temperature
120°C
Min. temperature
-10°C
Material
Brass dezincification, grey iron, stainless steel, PPS 40% glass
Gaskets EPDM, HNBR
Max. pressure kPa
400 kPa
Pressure class
PN20 (PV PN 25)

Preset

The PVM valve is easy to set on the knob using a 4 mm Allen key.
The PV valve is delivered ~ 1 turn open, which corresponds to the lower pressure in its range, for example, 5 kPa for a package that can be adjusted between 5-30 kPa and 20 kPa for packages that can be adjusted between 20-80 kPa.
Pre-setting is done by first adjusting the PV valve clockwise to increase the pressure and then counterclockwise to reduce the pressure.
The adjustment is made with the number of turns required according to the diagram.
The flow is verified by measuring the differential pressure across the STV valve.

Factory setting PV
Pressure range
5-30 kPa      Factory setting 5 kPa
20-60 kPa   Factory setting 20 kPa
20-80 kPa   Factory setting 20 kPa

Order designations

RSK – number Article number Designation Description
490 70 53 9001448 PVM 15 G 15 int. thread, 5-30 kPa
490 70 54 9001449 PVM 20 G20 int thread, 5-30 kPa
490 70 55 9001450 PVM 25 G25 int thread, 5-30 kPa
490 70 56 9001541 PVM 15 G15 int thread, 20-60 kPa
490 70 57 9001452 PVM 20 G20 int thread, 20-60 kPa
490 70 58 9001453 PVM 25 G25 int thread, 20-80 kPa
490 70 59 9001454 PVM 32 G32 int thread, 20-80 kPa
488 29 47 9001477 PVM 40 G40 int thread, 20-80 kPa
488 29 48 9001478 PVM 50 G50 int thread, 20-80 kPa