Static balancing valve Termojet DN20 (Rp 3/4") SBV

The Termojet SBV DN20 static balancing valve is a manual regulating fitting for precise hydraulic balancing of medium-capacity heating and cooling systems. Connection Rp 3/4" (internal thread), flow coefficient Kvs 5,39 m³/h at four spindle turns, maximum pressure PN 20 bar, temperature range –20…+120°C. Body — brass CW617N, EPDM seals, glycol compatibility up to 50%. The valve combines balancing, presetting, measurement, and shut-off in a single unit.

Technical Specifications

Operating Principle

The valve is installed on the return pipe of the balanced circuit or riser. Flow adjustment is performed by rotating the spindle: maximum flow capacity Kvs 5,39 m³/h is achieved at four full turns from the closed position. Integrated measuring nipples allow connection of a differential pressure gauge directly at the measurement point — without additional built-in elements. Once the calculated flow is reached, the spindle position is locked: the valve can be closed and reopened for maintenance without losing settings. The shut-off function allows circuit isolation without installing a separate valve.

Applications

• Risers in multi-apartment buildings. Rp 3/4" and Kvs 5,39 are typical parameters for a riser serving 3–6 apartments: balancing between risers eliminates overheating of upper floors and underheating of lower ones.
• Distribution from the boiler room manifold. A valve on each manifold branch ensures uniform flow distribution between circuits — underfloor heating, radiators, and DHW boiler.
• Cooling systems with fan coils. DN20 is suitable for balancing group branches of a chiller circuit — each zone receives the calculated coolant flow.
• Underfloor heating in large zones. For connecting a large-area underfloor manifold or balancing between two or three manifolds in a single system.
• Industrial and commercial facilities. Offices, retail spaces, production workshops with an extended two-pipe heating or cooling system.

Advantages of Termojet SBV DN20

• Kvs 5,39 m³/h — covers heat carrier flow for circuits with capacity up to 30–40 kW at a standard temperature differential of 10°C.
• PN 20 bar — elevated pressure rating with no restrictions for most commercial systems.
• Temperature range –20…+120°C — suitable for systems with any type of heat carrier, including antifreeze.
• Combined functionality — balancing, measurement, and shut-off in one body instead of three separate devices.
• Brass CW617N and EPDM seals — long-term reliable maintenance-free operation in glycol systems.

SBV DN20 and Heat Pump

When a heat pump operates in low-temperature mode (35–45°C), an unbalanced system leads to uneven heat distribution and overloading of the circuit pump. The Termojet SBV DN20 valve on each manifold branch or riser allows setting the precise flow as per design — the heat pump receives a stable hydraulic load, which increases its COP and extends the compressor service life. More about designing systems with a heat pump — on the Termojet heat pumps website.

Frequently Asked Questions

Why balance the system if there is a circulation pump?
The pump provides overall pressure in the system but does not regulate flow distribution between circuits. Without balancing, the heat carrier follows the path of least resistance — closer or shorter circuits receive excess flow, distant ones receive insufficient flow. Result: uneven heating, increased energy consumption, noise in the system. SBV DN20 fixes the required flow in each branch — and the system works as designed. For a larger diameter, see Balancing Valve SBV DN25 (Rp 1").

Can the valve be installed on the supply rather than the return?
Technically the valve can work on any pipe, but standard practice is installation on the return. This allows measuring the pressure differential across the entire circuit and simplifies maintenance: with the valve closed, the circuit is fully isolated. View the full range of balancing valves in Termojet Balancing Valves — Catalogue, smaller diameter — Balancing Valve SBV DN15 (Rp 1/2").