Area of use

The balancing valve STV is used to adjust and balance the flow in heating and cooling systems.

Description

STV is a flanged valve without a drain. The valve is equipped with self-sealing measuring sockets, placed at a 45° angle in relation to the wheel centre. The handwheel is equipped with a digital display. The valve is set at the desired flow or kv-value according to the diagram by means of the handwheel.
When the value of the valve is set, it can be locked. This is done by screwing down the inner spindel to its end position with a 6 mm Allen key. After locking, the valve can be closed but can not however be opened to a higher kv value than the one set.
The handwheel can be sealed according to the figure. To avoid turbulence which can affect the measuring accuracy the valve should not be assembled close to bends, branch lines and other valves directly before or after the valve according to the figure.

Flow measuring

The measuring instrument is connected to the measuring socket of the valve. The instrument is pre-programmed with the characteristics of all our adjustment valves and proving rings.
Other valve manufacturors’ data is also added to the instrument. Values for pressure drop and flow can be read directly on the display.
If you do not have access to the MMA instrument some other brands can be used. The flow can then be read from the pressure drop diagram found in the operating instructions.

Accuracy
Accuracy is greatest when the valve is fully open.
The smaller the opening, the importance of manufacturing tolerances increases, as variations in measurements are then greater percentage-wise. It is better to choose a valve that has a pre-set value above three turns.

kv-value

No turns DN65 DN80 DN100 DN125 DN150
1 2,8 5,5 8,0 10,0 18,0
2 5,1 9,5 13,5 22,0 33,0
3 9,6 13,5 19,0 33,0 68,0
4 20,0 18,5 33,0 63,0 130,0
5 35,5 29,5 67,0 106,0 186,0
6 51,0 49,0 99,5 150,0 246,0
7 66,0 68,5 125,0 194,0 294,0
8 78,5 85,0 150,0 236,0 340,0
9 87,0 98,0 170,0 273,0 385,0
10 93,5 110,0 190,0 301,0 425,0

Technical data

Pressure class
PN 16
Max temperature
120°C
Min temperature
-20°C
Max closing pressure
200 kPa
Min pressuredrop
5 kPa
Recommended pressure drop at rated valve
5-10 kPa
Material
Cast iron
Gaskets EPDM

Dimensions

Dim A B Weight/kg
DN 65 65 290 225 14
DN 80 80 310 240 20
DN 100 100 350 260 26
DN 125 125 400 290 40
DN 150 150 480 300 50

Preset

By means of the wheel, the valve is set at the desired flow or kv-value according to the diagram.
When the value of the valve is set, it is locked. This is done by screwingdown the inner spindle to its end position with a 6 mm Allen key. After locking, the valve can still be closed but cannot however be opened at a higher kv value than the one set.

Order designations

RSK nr. Art.nr Benämning Beskrivning
489 25 65 2250702 STV 65 Balancingvalve flanged without drain
489 25 66 2250802 STV 80 Balancingvalve flanged without drain
489 25 67 2250902 STV 100 Balancingvalve flanged without drain
489 25 68 2251002 STV 125 Balancingvalve flanged without drain
489 25 69 2251102 STV 150 Balancingvalve flanged without drain