Multiple interconnected energy production systems are a common solution to satisfy the energy demand of industrial processes. Such energy demand is usually the combination of various energy types such as heat and electricity. This implies the installation of different technologies able to produce one or multiple energy types, to satisfy all energy needs. However, multiple interconnected energy production systems may be extremely challenging from a management point of view. In this paper we investigate fundamental issues related to the management of multiple interconnected energy systems. We develop a tactical optimization model for the maintenance operations’ scheduling phase of Combined Heat and Power (CHP) plant. Specifically, we consider two types of cleanings operations, i.e., online cleaning and offline cleaning. Furthermore, we include a piecewise linear representation of the electric efficiency variation curve, accurately describing the impact of load and inlet air temperature inside the compressor on the electric efficiency of the CHP plant. Given the challenge in solving the tactical management model, we propose a heuristic algorithm. The heuristic works by solving the daily operational production scheduling problem, based on the final consumer’s demand and on the electricity market price. The aggregate information from the operational problem is used to derive maintenance decisions at a tactical level.