3-way mixing valve, threaded, straight-through, DN 40, PN6, kv=25 DR40GMLA

Application and Operation

The 3-way mixing valve DR40GMLA is used for regulating water temperature in heating circuits – primarily in systems with boilers or hot water storage tanks. Thanks to its three-way flow, it allows mixing of return water from the circuit with warmer water from the source, maintaining a constant, set temperature at the outlet. It is ideal where precise, continuous temperature control is required – e.g., for control based on external characteristics or in systems with buffering.

Construction and Materials

The housing is made of GG 20 cast iron (GJL-200), ensuring pressure resistance and long-term operation under humid and thermal conditions. The surface is protected with a primer paint – there is no additional coating, but it is sufficiently corrosion-resistant for domestic and commercial installations. The connections are internally threaded, DN 40, with an outer diameter of 40 mm and a length of 75 mm – all three ports have an identical design, without fittings. There is no possibility of mounting a tee for a four-way connection.

Performance and Reliability

The Kvs value is 25 m³/h – meaning the valve passes 25 cubic meters of water per hour at a pressure difference of 1 bar. The flow characteristic is linear for the bypass and equal-percentage for the main channel – ensuring predictable and stable mixing without sudden temperature spikes. Leakage does not exceed 1% of the Kvs value – i.e., very low leakage even at full closure. It operates safely at temperatures from 2 to 130 °C, and the maximum working pressure is PN6 (6 bar). This is not a valve for high-pressure district heating networks – but it works excellently in classic heating installations with gas or oil boilers.

Warranty and Advantages

The manufacturer's warranty is 5 years from the date of production – highlighting the structural stability and quality of workmanship. There is no need for additional filters before the valve – its construction is not prone to fouling under normal operation. Installation is simple: threaded connections allow direct connection to pipes without the need for flanges or special adapting elements.