What effect does high resistance in a furnace's electrical system have on operation?

High resistance in a furnace's electrical system has a significant impact on its operation, particularly leading to overheating. When resistance increases, it generates more heat due to the electrical energy being converted into thermal energy as it passes through the resistive components. This excessive heat can raise the temperature within the furnace components, potentially leading to component failure or damage over time.

Additionally, overheating can trigger safety mechanisms or limit switches designed to protect the furnace from damage, which could result in cycling issues or failure to operate. Maintaining optimal resistance levels is crucial for the efficient and safe operation of a furnace, ensuring that it functions within its designed parameters without the risks associated with overheating.