4 FM quick reads on Boilers
1. Boiler Safety: Annual Inspection Checklist
States and municipalities require boiler inspections. While some inspection requirements are becoming stricter, they do not cover the entire boiler system, and managers should consider them to be absolute minimum requirements.
Safe operation requires managers to go well beyond these minimal, legally mandated requirements to establish comprehensive inspection and testing programs. For example, at least once each year, operators should inspect all water-side and fire-side surfaces and remove corrosion, scale, and mud. They also should inspect refractory surfaces.
Annual inspections do more than meet the legal requirements of states and municipalities. They help to detect problems that are developing before they can cause costly damage to the boiler.
In addition to the mandated requirements, managers should ensure operators and technicians complete a number of regular tasks:
- They should examine the boiler or domestic water heater for code compliance at least once each year.
- They should identify and correct all installation deficiencies.
- They should inspect and test all safety and interlocks for proper operation.
- They should test the operation of the boiler's control system over a range of loads.
- They should test all shutoff valves annually to confirm they close and do not leak.
- They should check all interior surfaces during the boiler's annual inspection to ensure no localized overheating, erosion, or corrosion formation occurs.
2. Three common boiler safety devices
All boilers and domestic water heaters have a range of built-in devices to help ensure their safe operation. Like other components of building mechanical systems, they require periodic maintenance to ensure proper operation. Boiler operators and technicians should pay close attention to three key safety devices to protect personnel, equipment, and the facility:
- Safety valves. The safety valve is the most important safety device in a boiler or domestic hot-water system. It is designed to relieve internal pressure if a range of failures occurs within the system. Although it is simple in design and straightforward in operation, something as simple as corrosion or restricted flow within the valve and related piping can affect its operation.
- Water-level control and low-water fuel cutoff. Many systems combine these two separate boiler-safety functions into one unit. They are designed to ensure the water level within a boiler never falls below a predetermined amount. Should that situation occur, the system is designed to shut down the boiler by cutting off fuel. Proper functioning requires operators to make sure no build-up of sludge or scale exists within the system that would interfere with its detection and operation.
- Water-gauge glass. Even with a functioning water-level-control system, operators must verify the actual level of water in the system. Here, too, a build-up of sludge and scale can give false level indications.