Sequoia S

Sequoia S is an immersed electrode steam boiler from AERCO that delivers dependable, high-capacity steam with minimal maintenance and zero onsite emissions. Designed for large commercial and industrial facilities seeking to electrify their heating systems, Sequoia S is a clean, efficient alternative to traditional fossil fuel boilers.

Available in capacities from 2 MW to 70 MW, this fully electric unit operates directly at distribution voltages, eliminating the need for fuel storage, burners, or flue systems. A rugged, compact pressure vessel houses water-cooled electrodes that deliver rapid steam generation, reaching full output in as little as 30–40 minutes from a cold start or 1 minute from a hot start.

Ideal for facilities with steady steam loads, Sequoia S combines high efficiency, a 10:1 turndown ratio, and simplified installation for a seamless path toward sustainability and lower operational costs.

Features and Benefits

• Immersed electrode hot water boilers
• Available in 10 sizes from 2 MW to 70 MW
• Output: 100 to 300 psi steam (custom options available)
• Operates at 4.16 to 25 kV, 4-wire system)
• Up to 99.5% electrical-to-steam efficiency
• Immersed electrode design with grounded pressure vessel
• Full load from cold start in 30–40 minutes; hot start <1 minute
• Up to 10:1 turndown ratio with electronic modulation
• Integrated recirculation pump for electrode cooling
• Factory-assembled, pre-wired, and pressure-tested
• Minimal maintenance—no burners or combustion components
• Compatible with low-conductivity water for clean steam
• Optional PLC/HMI with touchscreen, remote monitoring, and diagnostics

Integrated Controls for Smart Operation
Each Sequoia S boiler comes equipped with a standalone, factory-programmed PLC control panel featuring a touchscreen HMI. The system provides full capacity tracking, safety interlocks, water level control, remote monitoring options, and data reporting to give operators complete visibility and peace of mind.

How it Works
The Sequoia S boiler uses the conductive and resistive properties of water to generate steam. An AC electrical current flows from the electrode through the water to a grounded counter-electrode, heating the water directly. The integrated recirculation pump maintains a constant cooling flow around the electrodes to ensure stable, safe performance and extend electrode life. Steam output is modulated by an electronically driven barrier shield that adjusts the exposed surface area of the electrode, enabling a high turndown ratio of up to 10:1.

The entire process is highly efficient, converting nearly all input electricity into usable thermal energy, with no combustion, no emissions, and minimal mechanical complexity.

System Built for Safety, Simplicity, and Speed

• Safety First — Pressure-rated vessel, grounded cage, and ASME-certified safety valves
• Smart Modulation — Motor-driven shield delivers smooth turndown and demand tracking
• Service Friendly — Manhole access, isolating valves, and intuitive instrumentation
• High Performance — Optimized flow paths and electrical integration for near-instant response

ESG and Decarbonization Goals
The Sequoia S boiler helps organizations meet aggressive decarbonization targets by eliminating on-site combustion and Scope 1 emissions. With no fuel storage, no stack, and no local pollutants, it is a clear choice for facilities transitioning to electric heating solutions that align with long-term ESG strategies and carbon reduction commitments.

Reduces Operating Costs Over Time
This electrode boilers convert up to 99.5% of electricity into steam, maximizing energy efficiency and minimizing waste. Automated controls reduce labor demands, and smart turndown capabilities help match output to real-time demand, minimizing unnecessary energy use. Facilities can further lower costs by operating during off-peak electricity hours.

Simplifies Installation
Sequoia S runs directly at distribution voltages, removing the need for fuel delivery infrastructure, stacks, economizers, or emission control systems. That means faster installations, lower capital costs, and less engineering complexity compared to traditional boiler systems.

Safe and Easy to Operate
With no flame, no fuel, and no combustion-related hazards, Sequoia S is inherently safer than conventional boilers. Electrode technology prevents operation without water, while the grounded pressure vessel adds an additional layer of electrical safety. All operations are controlled via an intuitive HMI and PLC system for user-friendly control and diagnostics.

Straightforward Maintenance, Reliable Operation
With minimal moving parts, no burners, and no fuel lines, maintenance is simplified. Long-life electrodes are continuously cooled by internal water circulation, extending service intervals. The result? Fewer unexpected shutdowns, greater uptime, and lower total cost of ownership.