Thanks for your question! I recommend looking into the Reference Guide (https://www.climateinteractive.org/wp-content/uploads/2021/03/En-ROADS_Reference_Guide_030321.pdf). Unfortunately, we aren't equipped to support users with a deep dive into the model's equations at this time.
Please see Attached PDF documents the Section references from EN-ROADS SIMULATOR REFERENCE GUIDE
The most important of course is the Climate Section:
The model climate is a fifth-order, linear system, with three negative feedback loops. Two loops govern the transport of heat from the atmosphere and surface ocean, while the third represents warming of the deep ocean. Deep ocean warming is a slow process, because the ocean has such a large heat capacity. If the deep ocean temperature is held constant, the response of the atmosphere and surface ocean to warming is first-order. (Page 343)