boilers  you  will  be  assigned  to  operate.  For  specific operating  instructions,  consult  the  manufacturer’s manual for the boiler concerned. Normal  Operation During normal operation of boilers, the operators have  two  major  responsibilities.  First  is  to  maintain proper water level at all times. If the water level is too low, tubes may overheat, blister, and rupture. If water level is too high, carry-over of water to the superheater tubes  may  damage  the  superheater  elements  and  the turbine. The second is to prevent loss of ignition when burning  fuel  is  in  suspension.  Maintain  safe  and efficient  combustion  conditions  in  the  furnace  and correct fuel-air ratios. Blowdown Establish  definite  intervals  for  blowing  down  the boiler,   depending   on   the   type   of   operation   and chemical  analysis  of  the  boiler  water.  During  regular operation,    never  blow  down  economizers  or water-cooled furnace walls. Blowdown valves on this type of equipment serve only as drain valves. Blowdown  should  be  at  reduced  or  moderate rates   of   steam   for   low   point   drains   or   blowdown valves. When the water glass is not in full view of the operator   blowing   down   a   boiler,   another   operator should  be  temporarily  assigned  to  observe  the  water glass and signal the operator handing the valves. For control  of  water  conditions  when  working,  use continuous  blowdown  to  maintain  the  proper concentration   at   all   times   and   to   prevent   blowing down  large  quantities  of  water  while  the  boiler  is operating  at  a  high  capacity. 1.  Flue-gas  temperature a. Keep the temperature low. b.   Temperature   should   be   about   150   degrees higher than temperature of steam produced. 2.  Flue-gas  analysis a.  Take  periodically. b. Maintain proper CO;! level for fuel used. 3.  Flame a. Should be long and lazy. b. Must not enter the tubes. c. Not dark and smoky. d.  Have  a  light  brown  haze  from  stack,  except gas. e.   When the fuel is oil, have a yellow flame with dark or almost smoky tips. 4.   Draft Boiler Makeup Water a. Usually 0.03-0.06 inch of water. Use  only  properly  treated  water  for  makeup,  and maintain  the  boiler  water  conditions  as  specified  in water  treatment  instructions.  Make  an  accurate  water analysis  at  specified  intervals.  Carefully  control  the blowdown and the addition of treatment chemicals to meet  the  manufacturer's  specifications. b.  Check  the  manufacturer‘s  recommendations. 5.  Makeup  feed a. Maintain low rate. b. Avoid excessive boiler blowdown. 6.  Insulation Soot Removal Remove soot from hoppers and pits at definitely established intervals, as necessary. a. Ensure boiler and lines are well insulated. 7.  Water  treatment a.   Carry out prescribed treatment of boiler water. Instrument Readings Establish   definite   intervals   for   observing   and recording  the  readings  on  all  important  instruments and controls. Be sure you obtain accurate readings-and see that the readings are recorded properly on the log sheet or other required record. OPERATING  CHECKS To  help  ensure  efficient  operation  of  the  boiler, operators  should  ensure  that  proper  operating  checks are  done  during  boiler  operations.  Operating  checks,  as shown in table E, appendix II, apply to most, if not all boilers. Keys to efficient boiler operation and performance are as follows: 2-22