Page 63 - Boiler_Operators_Handbook,_Second_Edition

48 Boiler Operator’s Handbook

written log, however, may only include a record of data Boiler outlet water temperature: Hot water heating
by shift or on a four or two-hour interval. There is little boilers are typically controlled to maintain this
value to hourly data other than requiring the operator to temperature. It is required for output calculations.
be within the vicinity of each piece of equipment every
hour. It’s a matter of professionalism, operators with a Boiler water flow: Hot water boilers, especially certain
sense of being a professional enter data in the log every types of HTHW boilers, require a controlled flow
hour to demonstrate that they’re watching the plant. of water. The value is required for output calcula-
tions and should also be monitored for reliability
Suggested Matter and Data to Record because minimal flow should trip a limit switch.
Here is an abbreviated list of things that should
be documented in the boiler plant log along with some Booster pump pressure: See condensate pump pressure.
good reasons for maintaining a record of the values or
information. It’s arranged in alphabetical order and Burner gas pressure: The gas pressure at the burner is
many of these items won’t apply to your plant so you indicative of input and should be monitored for
wouldn’t include them in your log. consistency relative to load. Increases in gas pres-
sure relative to load are indicative of plugging of or
Air heater outlet air temperature: Monitoring the heated damage to the gas burner. Decreases are indicative
air temperature along with flue gas inlet and outlet of failure or damage to the gas burner.
temperatures provide an indication of fouling of
the heat transfer surfaces, leakage past seals or Burner oil pressure: The oil pressure at the burner is
through corroded tubes, and other performance indicative of input and should be monitored for
problems with the air heater. consistency relative to load. Increases in oil pres-
sure relative to load are indicative of plugging of
Annual inspection: The operator’s narrative should re- or damage to the burner gun or the atomizing me-
cord the annual (bi-annual or fifth year in certain dium controls. Decreases are indicative of failure
jurisdictions and with certain types of pressure or damage to the burner gun or atomizing medium
vessels) inspection of the boilers and pressure ves- controls.
sels in the plant. Inspections are required by law
City water temperature/pressure: See makeup water
in every state so documenting that it happened is
imperative. Don’t rely on the inspector, some of
Combustibles: Monitoring the combustibles content of
whom have been known to lose paperwork. The
the flue gas can lead to early detection of burner
record should include the name of the National
problems and fuel air ratio control failure. Larger
Board Certified Inspector and any findings that
plants may actually control air to fuel ratio using
inspector relates to the operator.
combustibles and monitoring that value is very
important to them.
Blowdown heat exchanger drain temperature: This data
provides a means of calculating the cost of heat lost
Combustion air temperature: Frequently this is also the
to blowdown. The temperature is an indicator of
boiler room temperature. The combustion air tem-
the performance of the heat recovery system and
perature is the base for a boiler heat loss efficiency
blowdown/makeup relationship. The drain also
determination.
dumps to a sanitary sewer which, by Code and
law, can’t be higher than about 140°F so it’s also a Contractor’s activities: The operator’s narrative should
record of compliance. describe which contractors were in the plant,
when they were there, how many men, and what
Boiler inlet water temperature: For steam boilers it is an
they were working on. It wouldn’t hurt to list the
indication of heat lost in feedwater piping or heat
names of each of the contractor’s employees. Less
added by feedwater heaters and economizers. For
needs to be recorded if there’s a contractor’s log.
hot water boilers it is an indicator of load, required
Even if there is, the operator’s log should note the
for output calculations. The inlet temperature for
presence of the contractors as well, use a simpler
fluid heaters and vaporizers serves the same pur-
record such as “XYZ Contractors on site at 8:20
poses.
a.m.—seven men.”