Zone and mixing valves
Hardly any recent heating system with several sources and several heating circuits can do without zone and mixing valves. These valves make heating control easy and comfortable while keeping your energy bills low.
What are zone valves and what are they good for?
Zone valves control the flow direction into individual zones of hydraulic circuits (e.g. heating, solar or cooling systems, water distribution etc.). They are either two way or three way ones. A two-way valve is designed to just open or close individual hydraulic circuits, a 3-way valve acts like a rail switch – it diverts the flow from its one inlet into either of its two outlets depending on its state – if switched on or off. Zone valves are further divided by their use, max. and min. closing pressures, temperatures and fluid types, types of electric actuators and safety functions.
What are mixing valves and what are they good for?
Mixing valves are designed for mixing two fluids of different temperatures in such a ratio that the desired outgoing temperature is reached. They are either 3-way or 4-way ones. Three-way valves mix two inlets into one outlet and mixing is performed by throttling/opening the flow in either inlet. These valves are typically used for mixing heating water for heating circuits (floor heating, wall heating, radiators), or for mixing the return line in solid fuel boilers in order to avoid low-temperature corrosion.
In applications where a constant, non-restricted flow also into the mixing valve is needed, a four-way mixing valve shall be used. Such a valve will blend the fluid to the desired temperature while maintaining the flow rate on both its sides. A typical example is water blending in a line outgoing from a gas boiler where the flow rate shall be maintained, or in a return line for solid fuel boilers.
Mixing valves are further divided by their use, maximum pressures, temperatures and fluid types. They are usually supplied without electric actuator (for manual control only), the actuators need to be selected depending on the controller used (24 or 230 V, continuous control, 3-point control) and the required intervention speed (60-240s).