Benchmark NX

  • Condensing, gas-fired, fire tube boiler
  • Advanced Edge controller
  • 399 to 500 MBH

Technical Documents

Frequently Asked Questions


What is the AERCO Benchmark NX high-efficiency boiler?

The AERCO Benchmark NX is a condensing hot water boiler for closed-loop hydronic systems, available in 399 and 500 MBH input sizes. It combines a compact footprint with up to 97.4% efficiency, a stainless steel fire-tube heat exchanger, and a fully modulating burner.

What types of buildings and heating systems can use Benchmark NX?

Benchmark NX is designed for condensing applications in closed-loop hydronic systems and can operate as an individual boiler or as part of a modular boiler plant. Its compact design and 399 and 500 MBH capacity range support light commercial, multifamily, institutional, and other applications with right-sized heating loads.

How efficient is the Benchmark NX boiler?

Benchmark NX has a certified efficiency range of 87% to 97.4%. Its fully modulating burner provides up to a 10:1 turndown ratio, allowing boiler input to decrease to 10% of maximum capacity as the building load changes.

How does the Edge® Controller support boiler plant operation?

The Edge® Controller provides precise temperature control, variable-speed pump control, commissioning support, and on-board Boiler Sequencing Technology for up to 16 boilers. Control options include constant setpoint, indoor/outdoor reset, remote setpoint, 0–10V and 4–20mA signals, Modbus, and BACnet.

Can Benchmark NX connect to a building management system?

Yes. Benchmark NX includes integrated BACnet IP and BACnet MS/TP connectivity for communication with compatible building management systems. The Edge Controller also supports Modbus and can coordinate multiple boilers through the built-in sequencing controls.

What installation options does Benchmark NX provide for piping, fuel, and venting?

Benchmark NX supports variable primary flow installations, ducted combustion air, and operation with natural gas or propane. Acceptable vent materials include AL29-4C stainless steel, polypropylene, PVC, and CPVC, with 4-inch vent and air-intake connections.

What features support the durability and serviceability of Benchmark NX?

Benchmark NX uses a stainless steel fire-tube heat exchanger and provides easy-open access for service. It is also backed by a 10-year heat exchanger warranty and offers low NOx emissions capability of 20 ppm or less, depending on boiler capacity.