Save Energy with Boiler System Updates

Kewaunee Retrofit

Boiler system technologies have evolved dramatically over the last decade.  It was typical for a boiler system to take up the entire size of a mechanical room, while that’s still common, new boiler designs provide smaller footprints, more flexibility and efficiency opportunities for steam and hot water users. 

If your existing boiler system is in good condition, but suffers from dated burner or controls technology you can significantly improve your boiler’s performance, reduce energy usage and reduce emissions. Here are some boiler update opportunities to consider:  

Variable Speed drive – with the aid of variable speed drives (VSDs), pumps and motors can gain efficiency by enabling them to only operate as needed. The result, electrical consumption is reduced and there is less wear and tear on components. 

Parallel Positioning – if your boiler is using a single modulation motor with jackshafts to the fuel and air damper, your boiler may be operating with higher excess air than required, thus, reducing efficiency. Incorporating a parallel positioning system with dedicated actuators for the fuel and air valves can deliver up to 5% in energy savings. 

O2 Trim – another way to ensure peak efficiency is to use an oxygen sensor/transmitter in the exhaust gas. The sensor/transmitter continuously senses oxygen content and provides a signal to the controller that adjusts the air damper and/or fuel valve, maintaining a consistent oxygen concentration. This minimizes excess air while optimizing the air-to-fuel ratio.

Lead-Lag Control – incorporating lead-lag control of multiple boilers that are incrementally sized for the load can substantially reduce energy costs due to a reduction of boiler cycling. Remember, every time a boiler cycles off, it goes through a pre- and post-purging cycle before reigniting. This means that ambient air is blowing through and across the heating surfaces of the boiler for approximately two minutes, purging valuable BTUs into the atmosphere. 

Advanced Controls – Often called SCADA (supervisory control and data acquisition) systems, advanced control systems are PLC-based platforms incorporating burner management, combustion control and monitoring in one integrated package. By installing an advanced control system, a facility can expect to see better performance, enhanced safety, lower maintenance and reduced operating costs. 

The Cleaver-Brooks Hawk ICS boiler/burner management control offers monitoring, reporting and communication capabilities for commercial and industrial boiler systems – retrofit capable no matter the boiler manufacturer. The features of the Hawk ICS include parallel positioning, O2 trim, variable speed drive (combustion blower), draft control, lead/lag sequencing and much more.   

Burner – if your burner suffers from worn parts and outdated technology, updating your boiler with the aforementioned components is not going to entirely improve your efficiency issues. A newer burner will feature higher turndown abilities and lower excess air requirements. In addition to efficiency benefits, low and ultra-low emission burners will help meet emissions regulations and reduce environmental impact.

I have contracted the services of Thermal Tech Inc for over a decade. During that period I have worked closely with many of their technicians and office staff on a wide variety of projects. Some of these projects include the design and installation of burners & control systems. With these upgrades our efficiency has gone up and our fuel saving has increased by 8%.  As well as utilizing their welding Team to meet all ASME codes, piping and help with understanding and complying with regulatory agencies. 

– Wayne H, JLL-MST Steam Plant Lead, Jacksonville, FL
Kewaunee boiler retrofit

Contact Thermal Tech Inc for a boiler evaluation to determine what upgrades will best benefit your boiler system and reduce energy usage. 

Source:  Cleaver-Brooks – Efficiency Benefits of a Boiler System Upgrade, Hawk Brochure