NextGen CoolLinks: Telecom HVAC Control, Engineered for the Field

Building Management System — in partnership with Marvair

The CoolLinks Controller began as a custom solution developed in-house for a telecom customer. The initial order was thrilling: 12 units, hand-built on our engineers' desks. When a follow-up order for 400 units arrived a week later, the panic set in. That scramble became the foundation of a product now installed in roughly two-thirds of a major telecom provider's sites across the country.

Why telecom HVAC is a different problem

A telecom shelter isn't a typical commercial space. The equipment inside throws off a heavy heat load, and it depends on tight temperature and humidity control to stay reliable. Let the climate slip and you risk costly downtime or outright damage to critical infrastructure. On top of that, climate control is one of the largest operating expenses at every site, and many sites may exist in extremely remote areas that make regular service difficult.

Process/Approach

Prism partnered with industry leader Marvair to create a highly configurable and scalable climate control and monitoring system for wireless telecommunication shelters. Collaborating closely with Marvair’s experts, we identified the specific challenges and requirements of the project.

Utilizing our extensive embedded design experience, Prism developed a solution that not only meets the customer’s specific needs but also adapts to a broader range of applications and operating conditions.

Solution

CoolLinks is a fully custom, modular, wall-mounted controller that pulls a shelter's monitoring and control systems into one configurable platform. Custom-printed circuit boards sit in a rugged enclosure built for the demands of modern telecom environments.

Under the hood, a low-cost single-board computer works alongside multiple STM32 microcontrollers, running application software on Embedded Linux plus bare-metal applications written in C++. It speaks the protocols the industry already uses - Modbus/TCP, SNMP, and BACnet - over wired Ethernet for clean integration into customer networks. An onboard independent Wi-Fi network lets technicians connect and control the system from a laptop, tablet, or phone right at the site.

The platform can manage up to four independent HVAC systems, supports multiple analog temperature and humidity sensors for zone-level monitoring, and connects to HVAC equipment through both traditional hardwired interfaces and Ethernet. And because all software is field-updatable, the product keeps evolving with the customer instead of freezing at install.

For operators, that adds up to:

• Precise temperature control matched to telecom equipment needs

• A rugged design that holds up in harsh environments

• Easy integration with existing HVAC units and site infrastructure

• Remote monitoring and control that cuts down on site visits

Building Reliability from the Ground Up

The NextGen CoolLinks controller is manufactured in two facilities in Washington County, Alabama—McIntosh, opened in 2013, and Chatom, opened in 2021. Both sites adhere to strict quality standards to ensure that every unit meets rigorous performance criteria.

Each controller undergoes a comprehensive power-up and functional test before leaving the factory, guaranteeing reliable performance once deployed. With our history in deploying controls solutions, we know what it's like in the field - when a unit ships, the technician installing it needs to be supremely confident it will work out of the box. That's doubly true in telecom, where the destination might be the top of a mountain in Montana or a distribution warehouse hours from anywhere.

Results

The solution provided the customer with a competitive advantage, allowing Marvair to offer their end customer a superior product that significantly reduced shelter operation costs while expanding functionality. The configurability and adaptability of this solution have made it effective for a diverse range of equipment shelter types, including:

• Telecom Shelters

• Fiber Colocation Huts

• Distributed Data Centers

• Utility Battery Energy Storage Sites

Partnership Through Customer Support

Customer support for the NextGen CoolLinks controller is managed entirely in-house, fostering a genuine partnership rather than a simple vendor relationship. Technicians report immense satisfaction with this relationship, because they're talking with people who both understand these systems and what their needs are in the field.

The support team possesses in-depth knowledge of the product and understands the real-world challenges faced by telecom technicians.

When issues arise, customers receive prompt and knowledgeable assistance, which is crucial for remote sites where delays can be costly. The support team’s direct connection to engineering and production facilitates quick problem-solving and continuous product improvement.

Evolution Through Two Generations

The transition from the first to the second generation of CoolLinks controllers introduced several enhancements based on customer feedback and field experience:

• Enhanced user interface for easier setup and diagnostics

• Improved energy efficiency to reduce operating costs

• Increased compatibility with a wider range of HVAC units

• More robust communication options for remote management

These upgrades demonstrate a commitment to listening to customers and adapting to their evolving needs.

The result

The platform gave Marvair an immediate competitive edge — a superior product for their end customer that cut shelter operating costs while expanding what each site could do. And because CoolLinks was designed to be configurable and extensible, it's proven effective well beyond its first use case:

• Telecom shelters

• Fiber colocation huts

• Distributed data centers

• Utility battery energy storage sites

Looking ahead

The product keeps moving. The team is exploring enhanced data analytics and integration with emerging telecom infrastructure, all in service of the same goal it started with on an engineer's desk: dependable HVAC control that keeps critical networks up.

Interested in developing custom embedded systems for demanding industrial and telecom environments? Explore Prism's Embedded Solutions services to learn how we design, develop, and support reliable hardware and software platforms for mission-critical applications.