Buildings are responsible for as much as 40% of global carbon emissions. HVAC systems significantly contribute to those emissions in commercial buildings — producing anywhere from 40 to 60% of a building’s total energy use and carbon emissions. Because of this, managing the energy usage of HVAC systems is critical to ensuring a sustainable building.
However, because many HVAC systems rely on water to distribute heating and cooling, maintaining efficiency is more complex than with purely electrical systems. Consistent water pressure is essential for proper operation. Fluctuations can create imbalances, causing some areas to receive too much or too little water flow, leading to inefficiency and occupant discomfort. All hydronic HVAC systems need valves to control water flow and keep the system running smoothly. However, these devices are typically overlooked as an opportunity to improve sustainability and efficiency.
Limits of traditional control valves
The reality is that traditional control valves don’t provide the necessary capacity to contribute to sustainability goals or operational or energy efficiency. They generally use a measure of air leaving the valve to determine the valve’s position. This ignores factors such as water temperature or variations in flow or pressure. Proper sizing, installation, and maintenance can be complex and must be done manually by a test and balancing professional.
Their inflexibility adds to the challenge. Traditional valves must be precisely sized during the design phase to match the system’s load. Oversized valves lose precision, while undersized ones can’t keep up with demand. If the building’s heating or cooling needs evolve—say, due to renovations or new tenants—the valves often need replacing, driving up costs and complexity.
All this creates headaches for facility managers and building owners. Each control valve must be manually checked and maintained, often requiring opening ceiling panels and working on ladders. Beyond the higher installation and maintenance costs, this complexity can add to the risk of poor system performance or even system overflows.
The value of pressure-independent balancing control valves (PIBCVs)
Pressure Independent Control Valves (PIBCVs) tackle these challenges head-on, delivering efficiency, flexibility, and sustainability to hydronic HVAC systems. Unlike traditional valves, PICVs automatically adjust to pressure changes, ensuring consistent water flow without manual intervention. Here’s how they add value:
- Smarter Insights: PICVs can connect to building management systems, collecting data to reveal how the HVAC system is performing in real time.
- Enhanced Comfort: Precise flow control keeps temperatures steady, improving occupant satisfaction.
- Lower Emissions: By optimizing energy use, PICVs cut carbon footprints and support sustainability goals.
- Future-Ready Flexibility: They adapt to changing needs, paving the way for smart building upgrades.
By managing an HVAC system’s pressure changes and efficiency, the PIBCV can help customers efficiently manage their facilities and meet sustainability goals.
Why use PIBCV?
Pressure-independent balancing control valves can significantly improve operational energy efficiency, reducing energy costs by as much as 20% or more. They provide value throughout the design, installation, and operational phases through:
- Energy Savings: They can reduce operational energy costs by 20% or more by eliminating waste and optimizing flow.
- Simplified Design: Sizing is based on straightforward gallons-per-minute (GPM) ratings—no need for complex Valve Flow Coefficient (CV) calculations.
- Faster Setup: PICVs cut balancing and commissioning time, getting systems up and running with less effort.
- Precise Temperature Control: They respond quickly and accurately to maintain ideal conditions.
- Chiller and Pump Efficiency: Expect up to 30% better chiller performance and pump energy savings of up to 80% by preventing overflows, even under partial loads.
- Stable Design Delta-T: PIBCVs keep the temperature difference between incoming and outgoing water consistent, boosting efficiency and avoiding utility penalties.
- Consistent Pressure: They maintain steady differential pressure despite system fluctuations.
- Adjustable Flow: Settings can be tweaked to match minimum or maximum demand.
- Equipment Protection: By ensuring proper water flow, PICVs safeguard coils and heat exchangers from damage or inefficiency.
- Longer Lifespan: Reduced system oscillations mean less wear on actuators, extending their durability.
A pressure-independent balancing control valve uses new flow technology for automated flow balancing, with flow accuracy of +/- 95%. Using a PIBCV ensures a stable flow, keeping pressure consistent across the valve to improve efficiency, as it means the water is moving through heating or cooling at the right speed to be appropriately heated or cooled. It also avoids the risk of overflows, which can reduce efficiency and waste energy. This removes the need for traditional balancing valves at the unit.
Simplifying retrofits
There are additional benefits for retrofit applications. Older manual control valves don’t need to be removed or replaced—they can be left in place and set to be fully open, with the newly installed PIBCVs automatically adjusting the flow. There’s no need for manual control, although a balancer can be added if desired to control the flow rate. With this approach, there is no need to shut down and drain the entire system. This reduces the cost and complexity of the project.
If you are looking to modernize and future-proof your building, increase occupant comfort, and limit energy costs, adding PIBCVs to your hydronic HVAC system can help. Their functionality can be further enhanced with smart actuators, which we’ll examine in more detail in our next blog.
Want to dive deeper? Explore how PICVs can transform your building.
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