Enhancing HVAC System Design with Hydronic Fan Coils

In the HVAC industry, fan coil units (FCUs) are often perceived as just terminal units. However, these essential components play a crucial role because they directly interact with the air in any given space. This means that fan coils have a significant impact on indoor air quality, occupant comfort, and the whole HVAC system’s energy consumption.

Hydronic-powered FCUs deserve attention early in the design process to ensure optimal performance and efficiency. This approach enhances the effectiveness of the HVAC system and creates the ideal indoor climate for its users.

Hydronic fan coil statistics

Hydronic or water-powered fan coil units make up a significant portion of the global FCU market. This dominance and growing demand highlight why FCUs should be considered earlier in the design process. Understanding their role in HVAC systems is crucial for optimizing performance and efficiency.

Market Share

Hydronic (or water-based) fan coils account for approximately 60-70% of the total market.

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Growth Rate

The hydronic HVAC market, which includes fan coil units, is expected to grow at a compound annual growth rate (CAGR) of 6.3% from 2025 to 2030.

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Regional Popularity

Hydronic systems are popular in regions with firm energy efficiency regulations and green building standards, such as Europe and North America.

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Understanding the role of fan coils in HVAC systems

A hydronic fan coil unit, comprising a fan, a coil, and a filter, is an integral component of HVAC systems. It regulates the temperature within a space through heat exchange, making it critical to the overall performance and sustainability of HVAC systems.

The fan draws air from the room or a connected duct system. It then directs the air over the coil, which contains either hot or cold water. This coil is responsible for heating or cooling the air, depending on the desired temperature. A heat pump, central chiller, or boiler system supplies the water within the coil. As the air passes over the coil, it undergoes a heat exchange process, where it either absorbs heat from the coil (in cooling mode) or releases heat to the coil (in heating mode). The conditioned air is then filtered to remove dust and particles, enhancing indoor air quality, before being recirculated back into the room.

The entire process is regulated by a thermostat, handset, or controller, which controls the flow of water through the coil to maintain the set temperature. This efficient mechanism allows FCUs to provide precise temperature control, contributing to the overall comfort and energy efficiency of the HVAC system.

Benefits of early FCU integration into system design

Integrating hydronic fan coil units early in the HVAC design process can greatly enhance system performance and efficiency, especially in regions where FCU demand is rapidly increasing like Europe and North America. Key benefits include:

Energy Efficiency

Leveraging the superior energy efficiency of hydronic FCUs from the start can lead to significant energy savings.

Advanced Controls

FCUs that include control logic, like Polar Air’s Auto-Dynamic Balancing System, delivers significant advantages for the broader HVAC system like stabilizing ΔT.

Humidity Control

Considering FCUs with improved dehumidification features can maintain optimal humidity, preventing issues like mold growth.

Flexibility

Early planning provides flexibility to choose from various configurations like ceiling, floor, wall-mounted, and ducted units, ensuring seamless integration into architectural designs.

Improved Air Quality

Understanding the specific application health needs means FCUs with advanced filters can be considered. These enhance indoor air quality by removing dust, pollen, and other particles. Particularly important in schools, care facilities, and hospitals.

Cost-Effectiveness

Quality design means fewer components that could fail, reducing long-term maintenance costs. As HVAC systems typically account for up to 40% of a building’s energy usage [3], early consideration of FCUs can result in substantial cost savings.

Optimized FCU Selection

Early identification of needs means choosing the right fan coil (2-pipe for single-mode, 4-pipe for simultaneous heating/cooling), enhancing system efficiency. It also means the FCU can be customized to adapt to varying conditions like occupancy and usage.

Integration with BMS

Ensuring the FCU has relevant integration with other building management systems leads to improved energy efficiencies, easy control and a smarter, more responsive building environment.

Polar Air's Auto-Dynamic Balancing System

With its advanced ΔT Manager software, our Auto-Dynamic Balancing System, included with I-Type Control logic, ensures precise thermal regulation through intelligent monitoring and control of inlet and outlet temperatures. This approach stabilizes ΔT, optimizing energy use across chillers, boilers, and heat pumps while preventing inefficiencies like low ΔT syndrome.

How can Polar Air help with HVAC system design

Polar Air Select Software

Polar Air Select Software is an advanced tool developed to assist HVAC professionals in designing efficient systems. It is particularly useful for selecting and specifying fan coil units, ensuring they are integral components of the overall system.

Using this software early in the design process helps professionals choose the most appropriate units for any project, optimizing system performance and efficiency. The software streamlines the design process with fast, precise solutions tailored to specific project requirements.

Its user-friendly interface and customizable parameters make it valuable for both small and large facilities. The new submittals feature allows users to configure units directly within the platform and generate detailed PDFs, including dimensions, weight, performance data, and optional accessories.

This functionality saves time and simplifies workflow, making Polar Air Select Software an essential tool for HVAC professionals aiming to improve their design and selection processes.

Polar Air Pre-Sales Services

Consultation, Analysis & Assessment: Our team conducts thorough consultations to understand your project requirements and challenges, performing detailed analyses and assessments to ensure we provide you with the best solution.
Recommendations: Product, Issues, Installation: We provide tailored recommendations on product selection, capacities and loads, and installation best practices to optimize system performance.
Sales & Application Engineering Support: Our sales and engineering experts offer continuous support, helping you navigate product selections and application requirements.
System Design & Select Software: Utilizing our Polar Air Select Software, we assist in the early stages of system design, ensuring the most appropriate units are chosen for your project.
Pricing: Product, Logistics, Promotions: We offer competitive pricing options, including detailed logistics planning and discounts to meet your budgetary needs.
Training & Education: We provide comprehensive training programs, including product presentations, lunch and learn sessions, CPD visits, and ongoing education to keep you and your team informed.

Polar Air After-Sales Services

Technical Support: Our dedicated technical support team is available to assist with any questions or issues that arise, ensuring your FCU operates smoothly.
Maintenance & Troubleshooting: We offer guidance on maintenance practices and troubleshooting to extend the lifespan and reliability of your product.
Warranties & Spare Parts: We provide warranty coverage and a reliable supply of spare parts to ensure your product remains operational and efficient over time.
Training Programs: Continued access to training programs helps your team stay updated on the latest product features and best practices.
Resource Library: Access a comprehensive library of manuals, guides, and FAQs to support your ongoing needs.

These services are designed to provide HVAC professionals with the support they need at every stage of their project, ensuring optimal performance from start to finish.

Polar Air Fan Coil range

The Polar Air fan coil range highlights the importance of hydronic FCUs in HVAC systems because of their ability to enhance overall system performance and efficiency. With over 1800 configurations, our extensive selection includes ducted, ductless, console/universal, and specialty.

PDWSL – Slim ESP Ducted

The Polar Air Slim Low ESP ducted fan coils have been designed to meet the specific demands of performance, size, acoustics, low energy usage, ease of installation, and maintenance for low height concealed applications in buildings with limited ceiling spaces.

PDWD – Double Skin High ESP Ducted

The Polar Air Medium ESP ducted fan coil units have been specifically designed to satisfy high cooling capacity at medium external static pressure applications.

PCGH-3R – 4 Way Cassette

The Polar Air 4 way cassette fan coils have been designed to maximize product flexibility on site and in stock offering easy to remove front panels, filters and integrated drain pumps. The cassettes also feature plug and play one step access to power terminals and auxiliary contacts for quick and easy wiring.

PFWSL – Slim Floorstanding

The Polar Air Universal Floorstanding fan coil units with energy-efficient EC motors are meant for residential and commercial applications with a slim and elegant 135mm or 5-1/8 in-depth design.

PDWA – Medium ESP Ducted

The Polar Air Low ESP ducted fan coil units have been specifically designed to satisfy high cooling capacity at low external static pressure applications. With quiet operation, compact dimensions and low heights, these units are ideal for ceiling concealed installations even in buildings with limited ceiling spaces.

VAHU – Vertical Mini Air Handling Unit

The Polar Air Vertical Mini AHU fan coils have been specifically designed for Vertical (VAHU) installation and suitable for ducted air distribution.

PHW Highwall Fan Coil

The Polar Air PHW highwall fan coil units are an ideal climate solution for high wall-mount installation, designed to meet and exceed requirements for efficiency, quiet operation, and aesthetics.

HAHU – Horizontal Mini Air Handling Unit

The Polar Air Horizontal Mini Air handler fan coil units have been specifically designed for horizontal installations and suitable for ducted air distribution. Their design also reduces on-site installation time and labor costs.

PFWB(C) – Universal Console

The Polar Air universal floorstanding fan coil units suit applications that require units for surface, recessed, or ceiling mount installations, with decorative casings or for ceiling concealed.

Conclusion: Polar Air advocates for early fan coil consideration in HVAC system design

At Polar Air, we believe in setting ourselves apart by considering hydronic fan coil units early in the HVAC design process. This proactive approach ensures our FCUs are perfectly incorporated, leading to better performance, improved air quality, cost savings, and improved well-being for occupants, and ultimately contributing to the success and longevity of the entire HVAC system. By enhancing indoor air quality and comfort, we meet the essential needs of our clients.

In a market where client satisfaction, sustainability, and energy efficiency are crucial, our focus on early FCU integration demonstrates our commitment to providing advanced, customized climate solutions. Fan coil units are more than just components; they are key to creating effective and efficient HVAC systems.