Oil fired boilers and their control systems must conform to which UL standard?

Oil fired boilers and their control systems must conform to UL 726 because this standard specifically pertains to the safety and performance requirements for oil-fired appliances and their associated controls. UL 726 outlines the necessary criteria to ensure that oil-fired heating equipment operates safely and efficiently, which is crucial for preventing hazards such as fire or carbon monoxide exposure that can arise from faulty systems.

Each of the other standards mentioned relates to different types of equipment or aspects of safety that do not specifically address oil-fired boilers. For example, UL 837 pertains to the safety requirements for gas-fired and oil-fired space heaters, but does not cover boilers explicitly. UL 1995 deals with the safety of HVAC equipment, and UL 508 focuses on industrial control equipment. These standards do not encompass the specific needs and performance criteria set for oil-fired boiler systems and controls as defined in UL 726.