What must be in place if only one low-water fuel cutoff is used?

If only one low-water fuel cutoff is used, a manual reset is required to ensure that the system operates safely and effectively. The purpose of a low-water fuel cutoff is to prevent the boiler from operating without sufficient water, which could lead to overheating, damage, or even catastrophic failure. A manual reset means that once the low-water level condition is detected, the device must be manually reset by an operator before the burner can be restarted.

This is a critical safety measure because it ensures that the operator is actively informed of the low-water condition and has the opportunity to assess the situation before allowing the system to resume operation. It requires human intervention, which adds an additional layer of safety by preventing the boiler from automatically restarting in a potentially unsafe condition.

In contrast, options like an automatic reset do not provide the same level of operator awareness and intervention; high-pressure cutoff is more focused on preventing overpressure conditions rather than low-water scenarios, and continuous monitoring systems, while beneficial, do not substitute for the manual intervention that a manual reset necessitates in the case of a single low-water cutoff device.