Commercial Boiler Control Tune-Ups (CLOSED)

Update: August 2021

Researchers have wrapped up monitoring and analysis and are preparing the final report to disseminate the project’s results. The following are some highlights of their findings:

• Boiler temperature and staging control optimization achieved an average of 6.0% savings in schools and 10.3% savings in multifamily buildings.
• Paybacks were under one year for 10 of the 17 sites.
• An average of 66% of the initial savings persisted into the second year.

The report will also include specific recommendations for utility initiatives to capture these savings. 

View the final report

Overview

Commercial boiler tune-up programs currently provide about 8% of total portfolio savings for natural gas utilities in Minnesota. CIP boiler tune-up programs have primarily achieved savings through burner air-fuel ratio adjustments and have not explicitly addressed adjustments to boiler temperature and staging controls.

A recent CARD-funded study of commercial condensing boilers found that adjustment of boiler control settings can provide substantially more savings than traditional burner tune-ups. Boiler temperature and staging/modulation control adjustments were projected to provide more than three times the savings of burner tune-up adjustments. With the increasing dominance of high-efficiency condensing boilers in new construction and boiler replacement situations, expanding the scope of boiler tune-ups to include control optimization provides an important opportunity to update programs and increase their savings per participant. This project will quantify actual savings achieved through such control adjustments for condensing boilers. 

This project will develop and field test an expanded scope commercial boiler tune-up protocol that goes beyond burner adjustments, to provide a comprehensive review of adjustments to boiler control settings that increase energy savings. A protocol for performing commercial boiler control tune-ups will involve collaboration with a number of industry professionals.

Field tests will be conducted in approximately 20 buildings to evaluate costs, savings, operations, persistence, and market and implementation issues. This will provide information that utilities can use to plan CIP program additions or modifications that achieve more boiler “tune-up” savings towards their 1.5 percent savings goal, and can be used to add boiler control adjustment measure(s) to the Technical Reference Manual (TRM).