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CONDITION 5 - BOILER NOISE - CONTROL AND ADJUSTMENTS
A certain amount of operational noise is to be considered “NORMAL” when operating a PULSE BOILER. Most
“objectionable” noise occurs on start-up and is correctable by the procedures outlined in this section.
NORMAL OPERATION:
START-UP CHARACTERISTICS:
• Typically smooth/rapid ignition during initial ignition period, (1-2 seconds to establish operation).
• Start-up may include occasional “Stutter” (or “Puff” or “Pulse”) but, boiler quickly adjusts to a
balanced steady-state operation.
STEADY-STATE OPERATION:
• Produces an audible but steady “Hum” (like a muted motor sound) when listening closely at
exhaust terminal.
“OBJECTIONABLE” NOISE:
START-UP CHARACTERISTICS:
• Typically requires adjustment or changes to the boiler installation. If uncorrected may cause
unusual wear of boiler parts which also affect noise.
• Usually caused by “Delay” or “Dislocation” (fuel rich/fuel poor) of sustained ignition during start-up.
Ignition may correct itself or system may “Snuff-out” and retry (unsuccessful ignition). This is often
characterized by “Thud(s)” / ”Thump(s) / ”Pop(s) / ”Crack(s)” depending on severity of condition.
STEADY-STATE OPERATION:
• Sound/frequency levels produced at exhaust terminals or transmitted to structure (via piping, etc.),
are minimized by conforming to installation criteria/proper boiler adjustment/and trying exhaust
changes.
