How to Find the Most Efficient Boiler for Your Needs

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A third of an industrial facility’s energy bill can be directly attributed to its boiler room operations. Whether you’re using a temporary hot water heater system or a dedicated industrial boiler, any system inefficiencies can lead to higher energy costs. To achieve maximum efficiency, increase energy savings, and reduce emissions and operational costs in boiler systems, businesses have to consider the replacement of older boiler systems, retrofitting of existing boilers, and investing in temporary heating solutions.

The overall condition of a boiler is what determines if replacement or retrofitting is the best option. If your goal is to improve efficiency, you need to identify the problems causing energy inefficiency. One of the areas of improvement to focus on is in the boiler control systems. New developments in boiler controls have continued to create new opportunities for substantial efficiency gains in industrial boilers.

Below, we discuss the different boiler control options available for permanent or temporary hot water heater systems and what you should know about them before choosing the most efficient boiler for your needs.

Boilers with Parallel Positioning

What is Parallel Positioning?

Most boilers use a simple combustion control strategy known as jack-shaft control. It incorporates a single positioning motor that drives the fuel and air position devices in a boiler system via an interconnected jack-shaft. While this control method is simple and economical for small burners, it can be inefficient for large industrial boilers. The fixed position arrangement makes it hard for the burner to compensate for environmental changes such as fuel pressure, humidity, and air temperature, leading to burner or heater inefficiency.

To solve this problem, parallel positioning control systems are incorporated into the temporary hot water system or boiler. In this type of control system, fuel and air devices are separated and driven by individual positioners. This new control system is quickly becoming the alternative option to improve overall boiler combustion efficiency due to its ability to keep the optimum fuel-to-air ratio in sync, even in considerable boiler modulation.

Benefits of Parallel Positioning

  • Gives end users more flexibility in fuel/air ratio.
  • Can adapt to oxygen more efficiently than jackshaft controls.
  • Enables burners to fire multi-fuel at their optimal excess air.
  • Can be applied to larger boilers or temporary hot water heater systems.
  • Efficient in more sophisticated burners.
  • Potential energy savings of up to 5% can be realized.

Where Does It Fit Into the Boiler?

Parallel positioning is incorporated into the boiler control system and is the best way to replace the single jack-shaft system. It provides electronic firing rate control over the dedicated actuators for the fuel and air valves.

Which Boiler Makes and Models Have It?

Brand   Model
Raypak Hi Delta Boilers H6/H7 models
Williams & Davis Boilers Scotch Marine 2000D Series/3000W Series
Miura Boilers EX Series models

Boilers with Oxygen Trim

worker-860910_960_720.jpgWhat is Oxygen Trim?

Oxygen trim is a boiler combustion control scheme that makes use of a sensor/transmitter that continuously senses oxygen content in the exhaust gas stream. It provides a signal to the combustion controller to maintain a consistent oxygen concentration when there are environmental changes like relative humidity, ambient temperature, and barometric pressure. This ensures peak efficiency of boiler systems or your temporary hot water heater.

Benefits of Oxygen Trim

  • Helps maintains consistent oxygen concentration in varying environmental conditions.
  • Reduces CO2 emissions.
  • Finer adjustments can be applied to the fuel-air ratio to compensate for combustion changes in pressure, humidity, and fuel quality.
  • Extends boiler lifespan .
  • Adaptive trim control to cope with continually modulating burners.
  • Improves boiler efficiency.
  • Reduces maintenance and downtime due to reduced deposits on boiler or temporary hot water system tubes.

Where Does It Fit Into the Boiler?

Oxygen trim is added to the integrated combustion controller. It allows the combustion system to become a truly closed loop control system that reacts to changes in combustion variances instantly, leading to reduced boiler inefficiencies.

Which Boiler Makes and Models Have It?

Brand   Model
Hurst Boilers 4VT Cyclone Steam Boiler
Bryan Boilers RV Series
Cleaver Brooks CBND Series

Boiler with a Variable Speed Drive

What is Variable Speed Drive?

Variable Speed Drive (VSD) is the term used to describe controls that enable motors to operate only at the desired speed at a given moment, rather than at a constant rotational speed. While VSD is used in many types of motors, it’s widely used in industrial and commercial boiler feeds, temporary hot water heater pumps, and fans. By controlling the speed of motors, VSD can reduce energy consumption in boiler systems. It’s particularly effective in operational conditions that call for frequent low load periods.

Benefits of Variable Speed Drive

  • Leads to elimination of unnecessary energy consumption.
  • Helps tailor demand on the RPM to appropriate levels.
  • No more constant RPM .
  • Quieter operation and softer motor starts.
  • Decreases stress on rotating parts like shafts and bearings, thereby reducing maintenance costs and extending life.
  • Significant savings in the energy consumed by motors.

Where Does It Fit Into the Boiler?

Variable Speed Drive, also known as Variable Frequency Drives or inverters, are attached to motors in boiler pumps and fans to regulate their rotational speed and power supply. This helps to achieve better process control and reduced energy consumption in your fixed or temporary hot water system.

Which Boiler Makes and Models Have it?

Brand   Model
Cleaver Brooks ClearFire-H steam boiler
Sellers Boilers S-Series
Miura Boilers LX-Series

Boilers with Lead Lag Control

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What is Lead Lag Control?

Lead lag control helps sequence the operation of multiple boilers in a facility, matching system load. If you have a temporary hot water heater on standby, installing a lead lag control system will enable your boilers to operate at peak efficiency, reducing cycling and significantly reducing maintenance and downtime.

If your facility is frequently operating heavily, a lead lag system can help bring in secondary or temporary hot water boilers to help spread the load. When production slows down, the lead lag system automatically shuts off the secondary or temporary hot water system.

Benefits of Lead Lag Control

  • Complete automation of startup and shutdown of boilers.
  • Perfect for buildings with multiple boilers.
  • Reduces energy costs and increases overall efficiency.
  • Enables direct communication with energy management systems.
  • Precise control of steam or hot water supply for facilities.
  • Improves boiler life through efficient operational control.

Where Does It Fit Into the Boiler?

A lead lag boiler control or sequencer is a panel-mounted electronic device whose input comes from a temperature sensor that’s positioned to measure the temperature of the combined water flow of multiple boiler installations. Lead lag controllers mostly come as stand-alone devices.

Which Boiler Makes and Models Have it?

Brand   Model
ABCO Boilers Type DT and Type DTM Models
Fulton Rental Heaters FT-0240-C, 0400-C, 0600-C
Lattner Scotch Marine Models

Boilers with Advanced Controls

What are Advanced Controls?

Advanced boiler control systems are also referred to as SCADA systems (System Control and Diagnostic Annunciation), and incorporate burner combustion control, burner management, and monitoring in one integrated package. These PLC-based platforms are installed in boiler facilities to improve performance, enhance safety, and reduce operational and maintenance costs. They act as a robust plant optimization solution for plant owners.

Benefits of Advanced Controls

  • Advanced controls enable remote monitoring and control of boilers and temporary hot water heater systems via internal communication systems or email, SMS, or voicemail.
  • Ensure boiler operation within the set safety parameters.
  • Easier gathering of valuable information related to energy consumption, maintenance trigger points, and safety.
  • Automatic alerts to operators in case of boiler malfunction.
  • Overall improvement in boiler operation and maintenance.

Where Does It Fit Into the Boiler?

SCADA systems are networked to boiler control and burner management systems. They are designed to provide remote operation, alarm message display, graphic display of information, historical trending, report generation, and remote controller tuning from a single location.

Which Boiler Makes and Models Have it?

Brand   Model
Raypak Hi Delta Boilers Hi Delta® Hydronic Boiler
Hurst Boilers   Series 100
Fulton Boilers SRT Series Spiral-Rib Tubeless Boiler

Boilers with High-Efficiency Burners

806365224_b1f0d01606_b.jpgWhat Are High Efficiency Burners?

High-efficiency burners are designed to operate more efficiently than older burners. If you have been using your burner for more than 20 years, an upgrade is highly recommended. Older burners lose their effectiveness due to the wearing down of major components causing erratic combustion that lead to high energy costs.

Taking advantage of technological advances in burner designs like high turndown features and lead control ensures that you that your plant enjoys huge benefits.

Benefits of High-Efficiency Burners

  • Reduced emissions and improved turndown.
  • Reduced maintenance due to improved operational efficiency.
  • Works in tandem with multiple boiler lead lag control systems.
  • Increased energy savings due to a reduction in cycling.
  • Precise control capabilities.

Where Does It Fit Into the Boiler?

A high-efficiency burner is designed to maximize combustion efficiency in boilers while also minimizing the release of emissions. If you have an old boiler, replacing it with a more efficient one or even a temporary hot water system may be the best option. However, there are new technologies to upgrade existing boilers with high-efficiency burners that lead to major improvements in operational efficiency.

Which Boiler Makes and Models Have it?

Brand   Model
Miura Boilers Low NOx Series
Williams & Davis Boilers 2000D Series
Hurst Boilers Cyclone “Phase II”

Boilers with Heat Recovery

What is Heat Recovery?

Heat recovery in boiler systems serves to generate hot water or hot steam using the heat recovered from combustion chambers or burners in industrial or commercial boilers. Heat recovery helps improve energy efficiency in boilers. It can be incorporated in various ways:

Option 1: Non-Condensing Vent Stack

Adding a non-condensing vent stack economizer to a boiler system or temporary hot water heater helps transfer energy from the boiler exhaust gas to the boiler feed water. Usually, wasted heat is used to increase the temperature of the feed water before it enters the boiler, therefore increasing overall efficiency.

Option 2: Condensing Economizer

This can be incorporated with a non-condensing economizer in one package, capturing both latent and sensible energy from the flue gases that leave the boiler. This heat recovery combination helps save as much as 4% to 8% of normal fuel consumption.

Option 3: Blowdown Heat Recovery Unit

This is the most effective heat recovery method for wasted energy that results from continuous blowdown of TDS (Totally Dissolved Solids) in a boiler or a temporary hot water system. The unit transfers most of the heat to the feed water before it is sent back to the boiler’s feed tank. The rise in feed water temperature leads to improved efficiency and fuel savings.

Option 4: Flash Tank

This heat recovery method helps capture waste heat from blowdown processes and preheats cold makeup water. A flash tank economizer recycles most of the heat back into the boiler or temporary hot water heater and helps you reclaim a percentage of the blowdown water in the flash stream.

Benefits of Heat Recovery

  • Saves potentially wasted energy.
  • Integrated heat recovery leads to fuel savings.
  • Improves boiler efficiency.

Where Does It Fit Into the Boiler?

Heat recovery systems are installed in front of burners, heaters, or furnaces to capture any wasted energy that would otherwise be used to improve boiler efficiency.

Which Boiler Makes and Models Have it?

Brand   Model
Burnham Boilers Series 3 or Series 4S Steam Boilers/MPC
Laars Boilers 9600 CB Series
Mohican Boilers 4-Pass Wetback boiler

Installing Boiler Control Systems

1280px-KH_St_Elisabeth_2013_Technik_08.jpgWhen it comes to maximizing boiler efficiency, you’re most likely going to invest in boiler control systems for your existing boiler or temporary hot water heater. Unless you’re buying a new boiler, choosing the most efficient one for your needs will be more about selecting and installing systems that maximize efficiency and help you manage operations smoothly.

If you’re planning to install better and more efficient control systems for your boiler, the experienced and professional team at Manley’s Boiler, Inc. is ready to help you with the selection, purchase, and installation of boiler control systems.

Get in touch with us today to review the options we have to improve performance and efficiency for your boiler.