Standards Shape the Future for RTUs
Standards will take effect in two phases
LAS VEGAS — On Dec. 17, 2015, the U.S. Department of Energy (DOE) finalized new negotiated energy conservation standards for commercial air conditioners, heat pumps, and warm-air furnaces. According to the DOE, these new efficiency standards will save businesses $167 billion in energy costs over the lifetime of the equipment — more than any other efficiency standard issued to date.
The new rooftop unit (RTU) standards will take effect in two phases, increasing minimum efficiency by about 10 percent as of Jan. 1, 2018, and by 25-30 percent as of Jan. 1, 2023. Standards for new warm-air furnaces, which are typically installed in conjunction with commercial air conditioners, will also become effective in 2023.
Furthermore, the ANSI/AHRI 920 standard, “Rating Standard for DX Dedicated Outdoor-Air Units,” has added efficiency minimums to the ASHRAE 90.1 standard, so manufacturers are adjusting and preparing. Therefore, it’s not too surprising that the biggest trend with rooftop units and chillers at the 2017 AHR Expo was energy efficiency.
RTU manufacturers focused on meeting or exceeding these new government mandates with their newly developed equipment.
“Pushing equipment efficiency higher has gone from a trend to the norm,” said Mike Schires, senior product manager, Modine Mfg. Co. “Manufacturers are continually looking to either keep pace or stay ahead of the curve when it comes to constantly changing efficiency regulations, both current and future.”
Modine showcased its updated Atherion system at this year’s show. The 20-ton model of the Atherion achieves exceptional part-load efficiencies due to its use of modulating digital scroll compressors, electronic expansion valves (EXVs), modulating head pressure control, backward inclined airfoil plenum fans, and the selection of components that reduce air-side pressure drop.
“There’s a shift from full-load efficiency (EER) to part-load efficiency (IEER) minimums,” Schires said. “Fortunately, for Modine, we’ve been considering this since the the initial stages of the Atherion’s design. We’ve been highly focused on maximizing part-load efficiency because we know that is where the equipment operates most of the time.”
Trane’s Precedent Light-Commercial rooftop units with eFlex technology include 6- to 10-ton sizes of energy-efficient light commercial packaged rooftop units. Trane eFlex variable-speed compressors and fans precisely match output to the cooling demands of the space.
Another trend found in rooftop units is easier connectivity. Johnson Controls Inc.’s York XY 04 to 09 Direct Fit Packaged Heat Pump was updated this year and is now more efficient. This heat pump meets the ASHRAE 90.1 standard and is powered by Johnson Controls Smart Equipment, which allows contractors to connect to the unit through various smart devices with tools, such as their Mobile Access Portal (MAP) Gateway.
“Smart Equipment provides contractors with the ability to access, control, and troubleshoot HVAC issues without traveling to the site. They can see what a unit is doing from anywhere in the world using just the smart devices already in their possession,” said Jason Beke, commercial product manager, Johnson Controls Inc.
Daikin Applied’s remotely connected rooftop Rebel, Trailblazer, and Pathfinder units are now Intelligent Equipment-enabled, which provides customers and contractors greater visibility into their HVAC equipment.
The Trailblazer is designed for low-install costs and high performance, easing the installation process for contractors, while the Pathfinder, which was the winner of this year’s AHR Innovation Award in the cooling category, features variable volume ratio (VVR) technology that allows the chiller’s compressor to optimize performance for every condition, at every hour of the day, while improving efficiency levels.
“Being able to take that combination of rooftop unit and variable air volume (VAV) and the controls associated with it is a trend we’re seeing,” said Jim Macosko, product general manager, air handling, Daikin Applied. “At the contractor level, being able to install without necessarily bringing in a full-blown controls contractor is a great perk. Trying to get that dream of a plug- and-play VAV system with controls is something contractors want and have wanted for years. That is something we’re striving to do with our rooftop products and intelligent equipment — funnel it all into one system.”
Updates to ASHRAE 90.1 are going to increase efficiency requirements for chillers and are expected to significantly alter the future of chillers. However, a lot of companies are making a conscious effort to stay ahead of these requirements.
“ASHRAE is coming out with a new standard that is going to increase chillers’ efficiencies approximately 10 percent. Efficiency is usually our No. 1 design requirement, so we’re on the higher end of the scale. A lot of our products already meet that standard today,” said Ross Miglio, president, ClimaCool Corp.
ClimaCool debuted a simultaneous heating and cooling water-to-water heat recovery chiller with an integral air-cooled condenser that provides energy savings. Each module contains individual brazed-plate evaporators and brazed-plate condensers for maximum chilled water and hot water output in heat recovery mode. Integral air-cooled fans will only operate when there is an unequal cooling or heating building load for the operating modules.
Trane showcased the latest in its Series S CenTraVac Chiller Series, the CVHM model. Providing a small carbon footprint as well as a quiet sound level, the Series S line of chillers is part of the Ingersoll Rand EcoWise portfolio.
Chiller manufacturers are also striving to make the installation process as easy as possible. Whether it’s making it easier to break down, adjust, or fit into tight or small places, manufacturers are simplifying the installation process for chillers.
Due to its modular design, installation of Aermec’s new water-to-water chiller, the WWM, can be adapted to suit specific development needs while guaranteeing improved safety and reliability. As a result, the cooling capacity can be easily increased over time and at a limited cost.
“We’ve designed the product to have access only through the front, which allows the modules to be configured back to back in a single line against the wall or stacked. This allows us to put as much cooling tonnage in a square foot as you would see in a large centrifugal chiller,” said Richard Gerbe, cofounder, Highmark NY LLC. “Contractors love that this chiller can go through a standard door when you remove a piece. Additionally, the redundancy you get with all of the standard compressors is great. You could work on one of these modules while not impacting any of the other cooling in the plant.”
Carrier Corp.’s new AquaEdge 19DV Centrifugal chiller provides greater insight about the performance of the commercial heating and cooling system to building owners and facility managers due to its integrated controls. Carrier SMART Service provides remote connectivity and advanced analytics, so building owners and facility managers can get the best return on their heating and cooling investments.
“This option provides improved oversight of energy and maintenance expenses and supports initiatives that promote good environmental stewardship through reduced resource consumption,” said Mark Rabbia, product business manager, Carrier Corp.
Geoclima exhibited its new adiabatic chiller in Las Vegas. This new adiabatic evaporative system ensures a greater airflow toward the condenser coils, both on (closed pads) and off (opened pads) mode, which makes it possible to eliminate a great amount of unnecessary material in favor of more compact and efficient structures. These features reduces installation costs for contractors because it’s smaller in both weight and carbon footprint and the size is suitable for truck transportation.
Publication date: 2/27/2017