BOE Exam ECR and MCR of a boiler 28 May 202228 May 2022 Rate this post ECR and MCR of a boiler ECR means Economic Continuous Rating of any boiler. MCR means Maximum Continuous Rating of any boiler. The relation between ECR and MCR:- The Economic continuous rating (ECR) is most offend 70 to 80 % of maximum continuous rating (MCR) in any boiler. Post Views: 900