TM 5-3895-374-24-2 16. For   small   “On/Off”   burners   with   a   simplex   nozzle, adjustments consist primarily  of  attaining  correct  fuel/air ratios.  Adjustments should be set to obtain 11 - 12 ½% CO2  and  no  more  than  a  #2  smoke  (Bachrach).    The burner can usually be set to burn at a 0 smoke reading. Oil pump pressures will be set anywhere from 200 to 300 psig.  See page 31, Table 9 for additional information. 17. Fixed  Air  Low  Fire  Start  burners  with  simplex  nozzles require correct fuel/air ratios for  high  fire  and  should  be set with no more than a #2 smoke at high fire with 11 - 12 1/2%  CO2.    0  smoke  should  be  attainable.    Low  fire nozzle pressures are set to achieve smooth light off with the air dampers fixed in the operating (high fire) position. See page 31, Table 9 for additional information.  High fire nozzle pressures will be from 200 to 300 psig. 18. Low/High/Oft or Low/High/Low modes of operation (both having    automatic    air    dampers)    should    have    initial adjustments made at the light off position.  See Section 3 for  mechanical  operation  of  the  specific  system.    After the “light off” fuel/air adjustments are made (which on a Low/High/Low  oil  burner  is  the  same  as  the  “Low  Fire” position),  run  the  burner  to  the  high  fire  position  and make   adjustments    as    required    for    good    operation. Adjustments  should  provide  11  -  12  ½%  CO2  with  no more than a #2 smoke (0 smoke is usually attainable) at high fire and 8 - 10% CO2 with no more than a #2 smoke on    low    fire    (0    smoke    is    usually    attainable)    for Low/High/Low   systems.      For   systems   with   two-step pumps using simplex nozzles or internal bypass nozzles, the  oil  pressures  at  the  nozzle  supply  pump  gauge  port will generally be from 100 to 125 psig at low fire and 200 to 300 psig at high fire.  For systems with pumps that do not have the two-step operation and employ the internal bypass  nozzle,  the  nozzle  supply  pump  gauge  port  will generally  be  from  270  to  300  psig  at  both  low  and  high fires.    The  nozzle  bypass  line  pressure  at  low  fire  will generally be from 60 to 125 psig and 180 to 225 psig at high fire.  Tighten all linkages and permanently mark all settings.  See page 30, Table 8 and page 31, Table 9 for additional information. 19. Intermittently operate the burner until the  water  is  warm in the boiler, or follow specific initial firing recommendations    provided    by    the    heat    exchanger manufacturer. 20. See items 32 through 35 in this section for recommended limit    control    and    other    control    devices    operational checkout. Burners designed for Full Modulation operation.  After completing procedures   as   appropriate   in   items   1-14   above,   proceed   with modulating adjustments as follows: 21.    The modulating motor is connected by linkage to the air inlet dampers and a fuel metering valve located in the oil nozzle  return  line  controls  a  modulated  fuel  input  from low  to  high  fire.    Each  control  point  has  its  own  multi- position   arm,   so   that   proper   air/fuel   ratios   can   be achieved   throughout   the   entire   firing   range.      Initial adjustments should be made at the low fire position (low fuel/air flow).  All Power Flame burners are factory tested and  adjusted.    However,  to  determine  that  the  metering valve  is,  in  fact,  in  the  low  fire  position,  observe  the pointer on the metering valve shaft.  The pointer must be pointing toward the #6 or #7 position on the dial for North American valves, or 4½ to 9 on Hauck valves. As  the  burner  runs  from  low  to  high  fire,  it  will  proceed from the low fire setting towards the 0 position on the dial (i.e., the valve will be fully closed at high fire).  Refer to page 21, Fig.  28 for linkage adjustment information and page   20,   Fig.      27   for   adjustment   information   on   the Varicam characterized fuel metering system. 22. Turn the burner on and let it advance to the main flame light  off  position,  taking  action  as  necessary  to  hold  the linkage   at   the   low   fire   position   by   using   a   manual potentiometer or electrically disconnecting the modulating motor.  Power Flame burners are test fired at the  factory,  and  linkage  adjustments  for  modulation  are made at that time.  Note that the factory settings relate to good  operation  while  firing  into  open  test  pits,  and  will therefore   not   normally   relate   directly   to   the   absolute fuel/air  ratios  while  firing  under  specific  field  conditions. It  is  suggested  that  the  factory  settings  be  noted  and marked   on   the   linkage   prior   to   proceeding   with   final adjustment.  This will allow a return to those settings as initial reference points, if need be. 23. On  internal  bypass  nozzle  systems,  oil  pressure  at  the pump nozzle port will generally be between 270 and 300 psig  from  low  to  high  fire.    At  certain  input  ranges  of burner models C4 and C5, nozzle pressure may fall off to approximately 240 psig when in the low fire position.  For oil pressure settings on simplex nozzle systems, refer to page 31, Table 9. 24. On   internal   bypass   nozzle   systems,   typical   low   fire nozzle bypass line pressures will generally be in the area of 60 to 90 psig.  High fire nozzle bypass line pressures will  generally  be  in  the  range  of  200  to  225  psig,  but these  pressures  can  vary,  depending  upon  the  nozzle selected for a particular firing application.  Refer to page 30,  Table  8  for  specific  nozzle  bypass  line  pressures. Refer  to  page  31,  Table  9  for  simplex  nozzle  systems and pressures. 25. With  the  burner  in  the  “factory  set”  low  fire  position, adjust  air  and  fuel  linkage  to  good  fuel/air  ratio  low  fire settings  (8  -  10%  CO2  and  #0  -  #2  smoke  reading). Mark the linkage at the new settings. 26. Increase  the  firing  rate  to  the  midway  point.    Set  the fuel/air ratios to achieve good combustion values (9 11% CO2 and #O to #2 smoke reading).  Mark the linkage as a reference point for this new mid-fire position. 27. Increase the rate to the high fire position and repeat the tests done for the mid-point adjustment.  Results should be  in  the  area  of  12  ½%  CO2  and  no  more  than  #2 smoke.    The  metering  device  setting  and  air  damper openings should be marked and noted to obtain the high fire reference points. 28. Operate  the  modulating   lever   arm   on   the   modulating motor through the three previously determined reference points.    Minor  setting  modifications  may  be  required  to ensure that the reference points are acquired. 29. Tighten (finger tight) the hex bolt to the linkage rod at the swivel on the modulating motor driver arms, and run the motor through its full travel to ensure that linkage is “free” and   that   the   limits   on   the   metering   device   and   air dampers are not exceeded. 30. Intermittently operate the burner until the  water  is  warm in the boiler, or follow specific initial firing recommendations    provided    by    the    heat    exchanger manufacturer. 31. Tighten all linkages and permanently mark settings. (page 3 - 980)