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Boiler Efficiency Graphs & Comparisons

  • Boiler Power Plant Efficiency

  • Water Tube Boiler Efficiency

  • Energy Efficiency Rate

Savastat LC Energy Saving Boiler Controls

Savastat SC (Hydropath) electronic limescale inhibitor

We have found that significant improvements can be achieved in boiler efficiency by better controlling how the boiler operates in response to the changing conditions of a facility, as well as managing limescale within the piping system.  Combining technologies provides significant improvements in boiler power plant efficiency.

Boiler Power Plant Efficiency

The following Boiler Efficiency Graphs show run-time comparisons utilizing Savastat LC in a day-on, day-off test cycle over a period of seven days:

Savastat boiler efficiency comparison graph1

You can readily see the difference in the cycle patterns during the days Savastat LC is managing the boiler, by the varying mean temperatures.  Savastat LC closely manages the boiler based on actual demand.  The days LC is not controlling the boiler, the firing pattern is very regimented between the boiler set point, and cut-off temperature.

When we take a closer look to compare an on-day to an off-day:

Savastat boiler efficiency comparison graph1

Here we can better see that the mean temperature is "modulating" to accordance to system demand (load), whereas the off-day maintains a consistent internal boiler temperature regardless of the heating demand.

The mean temperature reduction of only a few degrees results in significant efficiency improvements, as the heat is transferred more effectively into the system at a wider differential.  Holding off the boiler when heat is not needed also significantly adds to the efficiency improvements achieved.  Typically a reduction in run-times of 20% or more are achieved.

Facility managers can conduct similar boiler efficiency analysis by tracking boiler run-times and day degree information.

Boiler Power Plant Efficiency & Limescale

The following graph shows how limescale effects water tube boiler efficiency:

Limescale efficiency loss graph

Similar losses are true in regard to fire tube boiler efficiency as well, only the scale forms on the outer surface of the tubing rather than inside the tubing.

ECMI and our Associates help our clients improve boiler operating efficiency in three ways: 

  1. By implementing the Savastat LC on compatible boiler systems to better manage boiler operation.

  2. By implementing HydroFLOW to improve heat exchange efficiency loss due to limescale build-up in the boiler system and heat exchangers throughout the facility.

  3. By implementing the Stack Draft Regulator on appliances to manage system flu draft losses.

By improving Boiler operating efficiency, boiler heat transfer efficiency, and stack drafting, significant energy savings can be achieved.  The combination of the systems can easily achieve savings in excess of 40% during a typical heating season.  Savastat LC implements "load compensation control" which enables the boiler to function more efficiently in real time based on the current ever-changing weather conditions and facility environment, HydroFLOW keeps the system free of limescale and operating at peak heat exchange efficiency, and the Stack Draft Regulator System optimizes appliance performance.

How Does ECMI Helps Clients Improve Boiler Power Plant Efficiency?

Savastat LC:

  • Is compatible with low pressure hot water heat loop system boilers

  • Will eliminate boiler short cycling

  • Will extend the boiler and equipment's lifecycle

  • Is easily installed with little down-time

  • Will provide a guaranteed 15% annual energy savings or a 24 month or less ROI.


  • Will remove limescale from inside the boiler and piping system.

  • Continues to keep limescale from forming within the system.

  • Keeps the boiler operating at peek efficiency.

  • Eliminates the need for frequently scheduled boiler cleaning, as well as the need and associated costs for expensive and environmentally unsafe chemicals. Example

Stack Draft Regulator System:

  • Brings appliance efficiency back near to the manufacturer's specifications

  • Eliminates heat losses due to negative drafting sucking the heat right out of the system

  • Provides a better flame pattern across the heat exchanger and eliminates "rope flame"

  • Cleaner burns means less soot and lower O2 readings in the stack

  • More efficient burns also means less fuel going up the stack

  • Keeps more heat in the system thus reducing burn cycles and burn frequency

  • Works with most any appliance with a flame and a stack!

  • VERY Significant savings when multiple appliances feed into a common stack!

Contact us so we can work with your organization to help improve boiler power plant efficiency in your facilities.

More on Improving Boiler efficiency


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