Technology

Raise the Roof


When it comes to today’s commercial HVAC industry, efficiency means everything. Xcelon is the only rooftop make-up air unit on the market that fuses innovative hydronic, condensing boiler technology with advanced air distribution methods for levels of efficiency up to 98%. In addition to this innovative combination, Xcelon’s self-contained, hydronic design and integrated control platform help produce maximum operating efficiencies that far surpass industry standards and expectations.


Hydronic Technology

Unlike other rooftop make-up air units that feature traditional clamshell or tubular heat exchangers, Xcelon is built with a high-efficiency condensing boiler paired with a hot water coil to transfer heat to the air stream. In addition to this unique and innovative pairing, Xcelon is designed with a factory charged closed propylene glycol loop as an intermediary heat transfer medium, removing the need for a water connection to the unit. The only connections required are ductwork, gas and electricity.

As a hydronic technology, Xcelon utilizes water as a transfer medium due to its inherent ability to hold more energy than air. By using water, Xcelon is able to transfer the same amount of heat in a much smaller surface area than air-to-air heat exchangers.

Benefits of Hydronic Technology:

  • Minimal footprint and maximum efficiency
  • Maximum efficiencies are maintained at the widest range of ambient and design conditions
  • Optimal user comfort is reached while reducing operating costs
  • VAV minimum CFM is only limited by the supply fan
  • No air stratification issues
  • A “green” technology with reduced emissions and high efficiency levels

Air Stratification

User comfort is critical component to any HVAC system design. However, most commercial HVAC systems have trouble scaling to larger sizing demands while maintaining efficiency. In order to accommodate various user comfort requirements, whether maintaining temperature for employee comfort or for factories with specific air temperature needs, Xcelon maintains a constant discharge air temperature to within +/-0.5° by virtually eliminating air stratification.


To do so, Xcelon’s glycol mixture in the hot water coil varies to maintain a constant discharge temperature. The resulting air is then passed through a fan located after the heating coil, mixing the air further. With an even air temperature leaving the unit, the risk of inaccurate sensor reading is greatly reduced and user comfort is maintained.

Xcelon Key Features and Benefits

  • 800 – 1,200 MBH heating capacity
  • +/-1°F temperature accuracy
  • Fully modulating gas valve and VFD
  • 10:1 turndown
  • Exclusive heat loss recovery system
  • Integrated HRT control platform
  • High efficiency hydronic condensing boiler
  • No separate water supply lines required
  • Factory charged closed propylene glycol loop
  • Built-in condensate trap and neutralization system (optional)
  • Plug-n-Play gas, electric and duct design
  • Operation at temperatures to -30°F
  • Service and installation friendly
  • Precision air flow/duct pressure control
  • Integral spring isolators for vibration control and quiet operation
  • 100°F maximum temperature rise
  • 4,501 – 10,000 CFM airflow
  • Low internal static pressure
  • No air stratification
  • BMS communication – Modbus standard LonWorks and BACnet optional
  • Designed for 100% outside air, optional return air and a variety of economizer controls
  • Available with optional 4 or 6 row DX or chilled water coil

Introducing Xcelon - Performance Over All

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