Steam boiler quarterly maintenance checklist

Steam trim, header and valve packing walked for leaks

No steam plume or hiss at packing glands, flanges, the header or trim connections, and no wet insulation or water marks on the floor under the boiler.

Boiler room steam traps checked for blow-through or backup

Traps on the header drip and boiler room lines read by temperature or ultrasound across the trap and compared with the last survey; a trap blowing steam or backed up is tagged.

Blowdown discharge route checked and people cleared first

Blowdown lines run to the blowoff tank or the site's safe discharge point, and anyone in the room is told and kept clear of the discharge before any valve is opened.

Gauge glass blown down and true level confirmed

Gauge glass blowdown valves cycled, water returning to the correct level cleanly, glass clear and not fouled or showing a false steady reading.

Try cocks opened to cross-check the glass level

Where try cocks are fitted, each opened in turn with the face kept out of the discharge: steam above the water line, water below, agreeing with the glass.

Low-water cutoff tested by lowering the level

Water level dropped through blowdown until the cutoff trips the burner, and the alarm activates, before the level reaches the danger point.

Auxiliary low-water cutoff blown down and trip checked

Where a second float cutoff is fitted, its chamber blown down per the manufacturer while firing and attended; the burner stops, and a manual reset type holds it off until reset.

Safety relief valve observed, not force-lifted if stuck

Valve and discharge piping checked for weeping, corrosion or a seized try-lever; a stuck valve is tagged for the service tech, never forced open by hand.

Operating pressure read and logged

Steam pressure gauge reading matches the operating range and the pressure control setpoint, logged against the prior visit for trending.

Pressure control settings read against the recorded settings

Operating control cut-in and differential and the high-limit setting read on their scales and matched to the log; the high limit sits below the safety valve set pressure. A mismatch is reported.

Blowdown performed and treatment checked

Bottom and surface blowdown done per the plant routine, chemical feed confirmed and a treatment sample showing dissolved solids within the target range.

Burner flame, combustion and feedwater observed

Steady flame with clean ignition and no rollout, feedwater pump and receiver cycling normally, condensate returning rather than running to drain.

Feedwater or condensate return pump checked where fitted

Running pump's seal and casing not leaking, coupling guard or shaft cover in place, no cavitation rattle or bearing noise, and motor temperature by IR compared with the last reading.

Blowdown valves shut tight and boiler left in automatic

Every blowdown and drain valve used on the round closed, the blowdown line cooling rather than passing, glass valves open and the burner cycling on the operating control.

Round results written to the plant log and reported

Cutoff trip results, pressure control settings and trap findings written into the plant log, with any deficiency reported to the owner before the tech leaves site.