Operating your boiler with an optimum amount of excess air will minimize heat loss up the stack and improve combustion efficiency. Combustion efficiency is a measure of how effectively the heat content of a fuel is transferred into usable heat. Ideally, a boiler would use just enough combustion air to burn all of the fuel, with no excess air. Excess air carries heat up the stack and reduces boiler efficiency. However, all burners require some excess air to ensure complete combustion.
The Boiler Tune-up tool estimates the energy savings associated with tuning your boiler to 4.0% exhaust O2 and cleaning the boiler water side heat exchanger surfaces to increase combustion efficiency. This process should be repeated once a year in order for your boiler to continue to operate at its peak efficiency.
This calculator was developed to provide a very general estimation of potential energy savings and simple payback. Any final economic decisions should be based upon the use of more extensive analytical tools.
For the Boiler Tune-up, users will need to input the following:
- Basic data about the boiler including control type, maximum and minimum firing rate, inlet and purge air temperature, air humidity ratio and purge cycle. Default values are provided for several of the inputs if the exact value is unknown.
- Steam system parameters such as steam system pressure range, steam system volume, steam pressure.
- Fuel type and fuel cost.
- Installation costs such as estimated equipment and labor cost.
- Boiler firing rates and stack conditions for high, medium, low, and standby conditions.
Based on input, the Boiler Tune-up will provide estimates of the current and potential combustion and boiler efficiency. The tool also estimates the energy savings associated with tuning your boiler to 4.0% exhaust O2 and cleaning the boiler water side heat exchanger surfaces to increase combustion efficiency.
Downloadable Version of the Boiler Tune-Up
This version of the tool can be downloaded and installed on a local computer to run the tool. System requirements to use the tool include:
- Microsoft Excel 2003 or newer
Download the offline version of the Boiler Tune-Up Tool
This tool is based on a similar tool created by the Oregon State University Efficiency Center. More information about the Oregon State University Efficiency Center can be found on the OSU Energy Efficiency Reference (EEREF) website at http://eeref.engr.oregonstate.edu/. Similar tools to the Boiler Tune-Up Tool can be found on the OSU Opportunity Templates website at http://eeref.engr.oregonstate.edu/Opportunities_with_Calculation_Sheets.