Establishing the most accurate air exhaust temperature from the Air Handling Unit requires the most accurate control of water flows into the heat exchangers for heating or cooling the entry air flow. In most cases a variable flow system is used for this. The best results, in both full- and partial load conditions, can be achieved by using Pressure Independent balancing and Control Valves (PICV). They are simply set to the required flow under full load conditions and function as automatic flow limiter. In partial load conditions the actuator accurately reduces the flow according needs. No overflow situation will occur, increasing the energy efficiency of the heat or cooling source.
For an alternative solution with a constant flow system, regular Motorized Control Valves and Manual Balancing valves to determine the maximum flow can be used.
To be able to service the control valves it is recommended to install manual shut-off valves.
Danfoss also offers a range of electrical actuators for dampers. They control the amount of air entering the air handling unit by positioning the dampers in any position between 0-90 degrees angle. These can cover a damper surface of up to 8 m2.
To protect frost sensitive parts of an Air Handling Unit, it is possible to install self-limiting electric heating cables. These increase their heat the output as the environment temperature reduces.
How we can help you
Complaint free indoor comfort
Accurate air temperature exhaust
Ease of service, maintenance and repairs
AB-QM pressure independent balancing and control valves
Take control on the water flows up to 442,000 liters per hour with Danfoss AB-QM pressure independent balancing and control valves.
Pipe tracing - cables
During winter, problems with frost in fresh water pipes, waste water pipes, cooling water pipes, supply water pipes and sprinkler systems can be avoided by heating the pipes internally or externally. The Danfoss systems provide either a constant wattage system or a self-limiting system.
Manual balancing valves
Manual balancing valves provide a static, basic balancing solution for many HVAC applications. The valves limit the flow through different parts in heating, cooling and domestic hot water systems. Since manual balancing valves can not react to changing conditions, the valves are recommended to be used in constant flow systems.
AB-QM Pressure Independent balancing and Control Valves (PICV) provide both a control functionality and dynamic balancing solution for HVAC heating and cooling systems. PICVs are designed for various types of terminal units and provide high indoor comfort and energy efficiency in public and commercial buildings.
Actuators for PICVs
To take advantage of the combined balancing and control features of Danfoss AB-QM it has to be equipped with actuators controlled by room thermostats or a Building Management System. Danfoss offers a broad range of actuators varying from thermal on-off to geared digital actuators with bus communication.