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Systems that distribute energy throughout the piping networks such as heating, ventilation, and air conditioning (HVAC), hydronics or hot water plumbing, all share a common important goal: to achieve balanced and equilibrium flow for all end points. The lack of such an equilibrium will inevitably lead to suboptimal performance and energy inefficiencies, which translates to inconvenience and a general unpleasant experience for the end user as well as additional costs for the facility owner. Balancing Valves as the name suggests, are valves specifically designed to combat and solve the issue of unbalanced flow in these systems. They function by adjusting specific flow rates for distribution to differing branches or circuits of the piping system, ensuring that each branch or circuit receives the desired flow rate required. Compared to traditional valves, balancing valves are equipped with adjustable features that allow operators to fine-tune flow rates according to specific requirements. Balancing valves come in different types as well, with the simpler manual static balancing valves to smarter dynamic control valves. In this article we will focus on the manual static balancing valves and a type of dynamic control valve: pressure independent control valves (PICV) used for the HVAC systems.
Manual Static Balancing Valves
The most simplistic technology of trying to achieve balanced systems is with manual static balancing valves. These valves are closest to traditional valves in the way they operate, controlling flow by varying the orifice openings of the valve via the obturator with the built-in control knob for fine tuning the flow settings of the valve. These valves are often accompanied by pressure tap points or flow meters to correctly assess the flow settings of the valves, such as the Caleffi 130 balancing valves that includes tap points with venturi devices for convenient pressure and flowrate measurements, or the Caleffi 132 balancing valves with built-in flowmeters. By placing these valves in each of the branch lines, flow can then be controlled and distributed accordingly, allowing the system to be more balanced on its flow distribution.
PICV
PICV are the more recent valves in terms of technological advancements. These valves such as the Caleffi 145 series are meant to achieve precise and high level of control over the flow balancing of systems. PICVs are balancing valves usually paired with an actuator, with the actuator serving to control the flow rate within a defined maximum set value. PICVs’ have the additional capability to ensure that flow is constant regardless of any changes in differential pressure conditions in the branch/circuit. With the modulating actuator attachment, the PICV will be able to further control the flow rate requirements of the branch/circuit in accordance with live demand, ensuring that optimal flow is being delivered to the end point.
Using Thermal Balancing Valves
When it comes to the installation of balancing valves, even though PICVs have a clear advantage in their capabilities to ensure proper balancing in thermal systems, a mix of fixed balancing valves and PICV can also be used in tandem to achieve a desirable result. However, the real advantage of PICVs is the ability to eliminate the need for an additional control valve that is often a requirement in some thermal systems such as hydronics (fan coil systems), potentially cutting down on installation costs as well. Having a well-balanced energy distribution system is crucial for not just comfort but also safety for users, and hospitality facilities that aim to provide top-tier services to its customers should consider proper balancing of their thermal systems; the potential power cost savings that a well-balanced system brings about are also points to keep in mind.
We at Val-Technik would be able to provide professional opinion on the appropriate setups for balancing valves and suggest optimal sizing for the valves to function effectively in thermal energy distribution systems.
For more information and consultation regarding the different types of balancing valves and their suitability for a system, please email us at sales@val-technik.com.sg or call 6742 2770.
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