Sizeable Commercial Units Need Installation and Service, Too
This year’s winners are Rheem, with the Rheem H2AC™ Rooftop Unit featuring eSync™ Integration; Johnson Controls, with the York® YVWA variable-speed water-cooled screw chiller; Daikin McQuay, with the Rebel DPS commercial rooftop system; and Danfoss Turbocor Compressors Inc., with the TT400 380V centrifugal compressor.
The Rheem H2AC™ Rooftop Unit featuring eSync™ Integration technology (RLHL-C Series and RKHL-C Series) unites a restaurant’s HVAC and water heating systems to achieve significant efficiencies, said the company. The product is designed specifically for full-service restaurants. The H2AC system works by switching over from a refrigerant-to-air system, to a refrigerant-to-water system when there is a demand for air conditioning and hot water. This is an energy-efficient option because the heat of the refrigerant is transferred to the water instead of rejected outside as in a normal air conditioning cycle. Using Rheem’s eSync Integration technology, the H2AC rooftop unit is able to preheat a restaurant’s cold water supply from as low as 55°F to as much as 125° — which substantially reduces water heating costs. The full H2AC solution consists of the rooftop unit, which is currently available in a 10-ton size; in the future, Rheem will offer this unit in 7.5-, 15-, and 20-ton models.
From an installation perspective, the Rheem H2AC Rooftop Unit featuring eSync Integration technology is sized according to standard load calculation methods, while the water heater is specified like any standard tank or tankless selection procedure. The H2AC rooftop unit is installed just like any standard rooftop unit; the only deviation is the required potable water piping to and from the hot-water system. To aid in servicing and maintaining the system, all major compartments can be accessed from the front of the unit, including the filter and electrical compartment, blower compartment, and outdoor section. To allow easy maintenance of the blower assembly, the entire assembly slides out by removing two ⅜-inch screws from the blower retention bracket. Allowing real-time monitoring and communication between rooftop units, the ClearControl™ system includes a rooftop unit controller, which is a solid-state, microprocessor-based control board that provides flexible control and extensive diagnostics for all unit functions. Access to extensive and accurate diagnostics can help contractors facilitate faster service calls. The unit features a single-slab, single-pass-designed evaporator and condenser coils, which facilitate easy cleaning for maintained high efficiencies. The evaporator and condenser motors are permanently lubricated for long-term convenience. The unit’s performance belt drive motor features variable pitch pulleys, which allow contractors to manually adjust the cfm and static for each application. A slide-out feature for fan assembly is installed for added service convenience.
The Johnson Controls’ York® YVWA variable-speed water-cooled screw chiller has a variable-speed drive that saves energy during the 99 percent of operating hours spent at off-design conditions, when building loads and/or tower-water temperatures are lower. It increases sustainability by using HFC-134a refrigerant, and the design reduces the number of potential leak points by 35 percent, said the company. The YVWA screw chiller is capable of handling a higher pressure lift than a centrifugal chiller; it can be used in both thermal-storage and heat-pump applications, while delivering the highest efficiencies available, the manufacturer stated.
Each unit is shipped as a completely assembled factory package, with all interconnecting refrigerant piping and internal wiring and ready for field installation. Specific points include single-point power connection; factory-mounted and -wired control transformer; factory-installed refrigerant isolation valves available as options; and unit-mounted circuit breaker and nonfused disconnect switch available as options.
The Daikin McQuay Rebel™ commercial rooftop systems deliver up to 19.5 integrated energy efficiency ratio (IEER). Rebel combines quality-manufactured McQuay equipment with advanced Daikin technologies: variable air volume (VAV) operation from 3-15 tons, variable-speed heat pump with hybrid (gas, electric, hot-water) heat options, variable-speed ECM motors on all fans, variable-speed inverter scroll compressor, electronic expansion valves, optional modulating hot gas reheat, and ultra-quiet composite condenser fans. Rebel is a VAV, air-to-air heat pump.
The MicroTech III unit controller with Open Choices feature provides interoperability with BACnet or LonMark communications for easy integration with BAS, unit-mounted keypad and display for better diagnostics and serviceability, 2- and 4-inch slideout filter racks for quick filter changeouts, one-quarter-turn door latches for easy maintenance access to components, variable-speed Daikin inverter scroll compressor for maintenance-free operation, full-perimeter forkable base rail with lifting lugs for easy manuevering and installation, and single-point power connection with separate control connections. Only direct-drive fans are used, which eliminates belt and bearing maintenance and also improves efficiency.
The TT400 380V model is an oil-free, variable-speed, magnetic-bearing centrifugal compressor. It uses HFC-134a refrigerant for an optimum environmental solution and provides outstanding part-load and full-load efficiency. The compressors include self-contained intelligent controls. The Danfoss Turbocor Compressors Inc. TT400 compressor has a capacity of 100–150 tons and is designed for mid-range, water-cooled chiller applications. The compressors are installed in applications such as hotels, hospitals, universities, office buildings, government institutions, retail, and industrial facilities.
The product is very easy to install, requires little maintenance, and is easily serviceable, said the company. The TT400 uses magnetic bearings so it has no moving parts that typically wear down. Also, because it’s oil-free, there’s no need to deal with oil pumps, switches, or oil analysis. The TT400 uses a compact, lightweight design that weighs around 260 pounds so it doesn’t require a crane or special installation equipment. It’s also an integrated unit with a variable-frequency drive, soft start, and other peripherals that are self-enclosed instead of requiring separate installation. Fault logs, diagnostics, and alarms are all included in the Service Monitoring Tool (SMT) software so that technicians can diagnose the problem quickly and easily and with minimal downtime.
Sidebar: 2012 Honorees — HVAC Commercial Equipment
Product: The Rheem H2AC™ Rooftop Unit featuring eSync™ Integration RLHL-C Series, RKHL-C Series
Manufacturer: Johnson Controls Inc.,
Engineered Systems Div.
Product: York® YVWA variable-speed water-cooled screw chiller
Manufacturer: Daikin McQuay
Product: Rebel DPS
Manufacturer: Danfoss Turbocor Compressors Inc.
Product: TT400 380V
Publication date: 7/9/2012