HTS Eclipse – AH-MA DualBlock (AHMA-DB) Duct Burner Series

Overview

The AH-MA DualBlock (AHMA-DB) is a modular, forced draft duct burner series designed to operate at the core of an airflow stream — mounted either inside or outside the duct. Based on the DualBlock mixing concept, combustion air is supplied by an integrated or remote blower that is completely independent of the process airflow, allowing the burner to deliver extremely clean combustion across a wide range of process conditions.

The AHMA-DB series covers a capacity range of 500,000 to 28,000,000 Btu/h (147 to 8,200 kW) with a turndown ratio greater than 20:1. Its modular construction supports multiple geometric configurations — including straight sections, double-T, and cross sections — making it adaptable to a wide variety of duct and furnace geometries.

Features & Benefits

• Capacity range of 500,000 to 28,000,000 Btu/h (147 to 8,200 kW) covers a broad range of industrial air heating applications
• Turndown ratio greater than 20:1 (max to min power) enables precise process temperature control
• DualBlock mixing concept — combustion air is completely independent of the process airflow, delivering clean combustion even in variable-flow, high-humidity, or low-oxygen environments
• Modular design with straight, double-T, and cross-section geometries for flexible duct and furnace configurations
• Integrated or remote blower options — 50 Hz IEC (CE) or 60 Hz NEMA (UL/CSA) motor ratings available
• Left-hand or right-hand gas piping with BSP or NPT threaded connections
• Stainless steel construction for durability in high-temperature process environments
• Motorized butterfly valve controls fuel flow only; burner air side remains fixed for simplified control architecture
• Air filter with internal flow adjustment and air inlet with adjustment/protection grid included
• Air flow switch available to meet NFPA requirements for air pressure monitoring

Technical Specifications

• Capacity range: 500,000 to 28,000,000 Btu/h (147 to 8,200 kW)
• Turndown ratio: greater than 20:1
• Fuels: natural gas, propane, butane
• Maximum air supply temperature: ≤250°F (121°C)
• Ignition: direct spark (smaller models below DB0400L) or spark-ignited built-in pilot (larger models)
• Flame supervision: flame rod or UV scanner — must be compatible with the monitoring control and comply with applicable codes
• Actuator requirements: 90° stroke, continuous or high/low modulating, reversible; ≤2 rpm (≈30 s/90°), ≥25 in-lb (2.8 Nm) torque
• Gas pipe connections: left-hand or right-hand; BSP or NPT threaded
• Blower options: integrated (mounted on burner) or remote; 50 Hz IEC/CE or 60 Hz NEMA/UL/CSA motors
• Mounting: external wall/duct mounting or internal mounting with fixing plate
• Material: stainless steel
• Control method: motorized butterfly valve modulates fuel only; air side is fixed

Applications

• Industrial duct heating and direct-fired air make-up systems
• Ovens and dryers with variable airflow, high humidity, or low oxygen content
• Furnaces requiring clean combustion independent of process air conditions
• Process air heating in manufacturing, food processing, and drying applications
• Installations requiring duct depression or light overpressure operating conditions

Models / Configurations

• DB0050L – Straight (L) section; smallest capacity model in the series
• DB0100L – Straight (L) section
• DB0200L – Straight (L) section
• DB0300L – Straight (L) section
• DB0400L – Straight (L) section; transition to spark-ignited pilot ignition at this size and above
• DB0500L – Straight (L) section
• DB0600L – Straight (L) section
• DB0700C – Cross (C) section geometry
• DB0800L – Straight (L) section
• DB0800T – Double-T (T) section geometry
• DB1200L – Straight (L) section
• DB1200T – Double-T (T) section geometry
• DB1500C – Cross (C) section geometry
• DB1600L – Straight (L) section
• DB1600T – Double-T (T) section geometry
• DB2000T – Double-T (T) section geometry
• DB2400T – Double-T (T) section geometry
• DB2500C – Cross (C) section geometry
• DB2800T – Double-T (T) section geometry; largest model in the series

AH-MA DualBlock Accessories

• Air filter with internal flow adjustment — included with burner assembly
• Air inlet adjustment/protection grid — included with burner assembly
• Air flow switch — for NFPA air pressure monitoring compliance
• Integrated blower — 50 Hz IEC (CE) or 60 Hz NEMA (UL/CSA) motor options
• Remote blower — for installations where the fan must be located away from the burner body
• Motorized butterfly valve — for fuel-only modulation control
• Flame rod or UV scanner — for flame supervision; refer to Honeywell Thermal Solutions compatible controls

Documentation