Where must a thermal cut-off switch be installed in relation to the burner circuit?

The requirement for a thermal cut-off switch to be placed at the highest point with the thermal element pointed down is crucial for ensuring its effective operation. This positioning allows the thermal cut-off switch to accurately detect the rise in temperature, which is essential for shutting down the burner in the event of overheating. By situating the thermal element at the highest point, it is more likely to respond promptly to the heat generated by any malfunction or failure within the heating system.

Furthermore, having the thermal element pointed down optimizes the exposure to heat, thereby enhancing the responsiveness of the switch. This arrangement minimizes the risk of overheating without the device intervening, making it a critical part of safety mechanisms in oil-fired heating systems. Proper installation in this manner ensures that the system operates safely and efficiently, complying with established safety standards.