Q:  I have a little doubt about the IPMVP Option to choose. The ECM I'm talking about is the implementation of a new algorithm to control and regulate the heat delivered by centralized haeting systems of condominiums, in order to reduce the natural gas consumption. The ECM can be turned on and off easily, so I would use the adjacent measurement periods method explained in the paragraph 5.4.3 of Core Concepts. But with which option? I thought about Option B, since we can test the algorithm in lab with a certain energy demand and we can measure the heat delivered by the generator and the natural gas supplied to it. Is it correct?

A: Yes, Option B Retrofit-Isolation All Parameter Measurement, would be the most suitable Option for the described situation and proposed methodology. As stated in your comment, the critical item is to keep the conditions (heating load, etc) constant under both measurement periods.