Efficient Control of Flow And Temperature In HVAC Heating And Cooling Systems

The Danfoss AB-QM Pressure Independent Control Valve (PICV) was the first of its kind control valve for HVAC heating and cooling applications in order to provide efficient control of flow and temperature. It provides a perfect flow limiter and a control valve in one compact package.

Finding ways to make commercial buildings and venues more energy efficient is a critical step in the journey to a decarbonised future. To achieve this goal then the buildings of the future, whether old or new, need to be adapted to be more climate-friendly, without compromising comfort for the occupants.

One of the most cost-effective measures to reduce energy demand is optimising HVAC and technical building systems. As heating and cooling accounts for up to 80% of a building’s energy consumption, focusing on energy efficiency opportunities on this aspect of our existing buildings.

The Danfoss AB-QM is an all-in-one balancing valve and differential pressure controller (PICV) that combines high accuracy and durability with market leading user-friendliness providing 100 percent valve authority, accurate flow limitation and precise system control of hydronic systems. The design of the AB-QM is fully geared towards making your project run on time and on budget while delivering the most efficient HVAC system. Due to the membrane design the valves are less susceptible to blockage. 100% built in control valve authority allows lower pump head than traditional setup, minimising energy consumption. 

The flow can easily be set to the needed amount by using a 20-100% scale. Simply, setting the design flow replaces traditional commissioning processes, gives a much more accurate control. This ensures that the flow does not exceed the set point and prevents overflow by the pumps. By controlling the flow to the pre-set scale, a low pressure differential is then kept by the internal diaphragm. This ensures that the flow does not exceed the set point and prevents overflow by the pumps. By keeping the flow at a constant efficient rate, the temperature provided to a room will not exceed dramatic tolerances and keep heating bills at a viable level. All of this creates cost savings on the installation and a more efficient system for both the installer and end user.

The AB-QMs are available in connection sizes from 10-50mm with a union connection style (threaded) and then 65-250mm are all supplied with a PN16 Flanged connection. Each size of AB-QM has predetermined flow ranges that the valves can be set to which is also part of sizing up what Valve to use, not just matching your pipework size. Each size of AB-QM has predetermined flow ranges that the valves can be set to which is also part of sizing up what Valve to use, not just matching your pipework size.

The AB-QM are mainly used for air handling units, climate ceilings, fan-coil units and other terminal units in HVAC heating and cooling systems.

AB-QM can be upgraded to work as a PICV by adding an actuator. We offer four different types of actuators to suit the AB-QM range, varying in their operation between On/Off, 0-10 Volt, 4-20ma or floating point and the choice between these will depend on the control strategy. Hydronic balance is maintained without allowing overflow as the AB-QM will control the flow. This functionality would normally be controlled by two separate valves so by incorporating it into one device, a further cost saving is made along with the efficiency obtained. 

Features and Benefits of AB-QM Pressure Independent Control Valve (PICV)

Stable Room Temperature

Eliminating the overflow situations at partial load conditions has a significant effect on the stability of the room temperature

Improved Indoor Comfort

With the stable room temperature, the indoor comfort increases. Required temperatures are accurately met, increasing the productivity of office employees or benefitting the experience of hotel guests.

Reduced Maintenance Costs

As the pressure-independent valves ensure perfect working conditions, the actuators mounted on them require fewer movements to keep the temperature stable. This increases the lifetime value of the actuators and reduces the maintenance costs