P99 LOW PRESSURE BOILER SIMPLIFIED REVISION SUMMARY

P99 LOW PRESSURE BOILER
SIMPLIFIED REVISION SUMMARY

Pressure Control
A switch that starts the burner, controls the firing rate, or
shuts down the burner based on steam pressure.
Operating Control
a pressure control that senses steam pressure and
automatically signals the burner to initiate the start-up
sequencer when steam pressure is needed and initiate the
burner shutdown sequence when steam demand is met.
High Limit Control
A pressure control that senses steam pressure and
automatically shuts down the burner if the operating
control fails
Modulating Control
A pressure control that works with the operating control to
vary the burner firing rate.
Condensate return tank
A boiler accessory that collects condensate returned from
heating units.
Vacuum pump
A boiler accessory that produces a negative pressure on
condensate return lines to draw condensate back from the
system.
Volatility
The ability of a substance to produce combustible vapors.
Boiler Operation Theory