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Steam Boiler - Exquisite Heat

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					        For Steam Boilers
& Hot Air, Fresh Air, et al.
   Thermostat Demand Analysis over time resets
    burner fire time for steam boiler.

   This will remove the leads and lags
    associated with the over and under steam
    value.

   Interior space thermostat analysis anticipates
    needed heat replacement precisely.
    Thermostat Analysis over time

      60 data points

1
0
                       18 red OFF points   41 green ON points


     41 green ON points
    60 Total sample points        =.6833 = 68%
                                   =
Thermostat analysis was 68 % of the
hour. The Ideal Demand Analysis we
desire is 60% Thermostat call
Subtract the .68-.60=.8 (Time Change
Factor) x 3 (minute Increment factor) =
+2.4 Minutes
If the old fire cycle time was 30 minutes,
we add 2.4= 32.4 minutes.
Demonstrate negative time change.
   Limits of maximum and minimum burner
    fire times.
   Time limit avoid boiler fire short cycle and
    allow for radiator catch up..
   All firings are thermostat initiated, and
    system pressure control limited.
   Initial start up fire times are determined by
    how long it takes to meet system pressure
    controls from a cold start.
Fire time adjustments
   Controller demand analysis (previously
    discussed) resets fire times, from hour to
    hour.
   Burner fire time will be increased or
    decreased at the end of each analysis period (
    60 min.) in order to meet the ideal thermostat
    demand ratio. (60%). On mild days this may
    well allow comfort satisfaction at lower than
    system pressure limit at the boiler.
   Radiators may well heat ½ way across.
         Fire time adjusts to satisfy Ideal Demand rate
    80                                                      90 min
    70                                                      45 min




                                                                      adjustment
                        X            X
  60%     o
          X           o o        o       o Xo
                                         X              o   30 min
    50            X                                 X
    40                       X                              15 min
    30
                                                             10 min
IDR %         1       2     3 4 5           6   7       8

                            Time in hours
Start-up fire time = the time it takes
 to satisfy pressure limit from a cold
                start. (15-90 minutes)

       Boiler pressure controls and
thermostat satisfaction can over ride
                        the fire time.
   Test pressure gauges and pressure control.
     Boiler should be making steam within 30-45 minutes.
    If not the boiler may be undersized.
   Check that boiler burner rate is high enough to
    produce good steam. (see boiler instructions)
   Analyze burner for proper firing and minimum excess
    air. ( CO2 %, stack temperature.)
   Check chimney flue, piping insulation, vents, traps,
    condensate return lines and boiler water level.
   The amount of time it takes to recover to
    steam delivery after a break.

   10-40 minutes

   Minimum    = Fire Time 10 min.
   Each building has its own rhythm.

   Factory settings can be adjusted if needed by
    the installer.
   The goal is to have the thermostat satisfied
    into the break.

   There are savings and comfort advantages
    as the thermostat is satisfied after the
    burner is off.

   The thermostat overrides all calls for burner
    firing. All control points operate in series.
   the thermostat does not call
 If
 heat for more than one hour the
 controller sets back to “Start up
 time”, at thermostat activation.
 Boiler can be shut down by
 pressure, thermostat, or
 controller analysis time.
   Maximum Burner Time 45-90 minutes

   Fixed break time 10-90 minutes.

   Start up burn time: 20, 30, 45,   60, 90 min.

   Min Burn time : 10 minutes.(short cycle prev.)
   Ideal demand ratio .5, .6, .7, .8
   Analysis time: 40, 60, 90 minutes
   Thermostat activity analysis within the hour
    will determine the increase or decrease
    adjustment of the burner fire time in the
    following hour.

   Actual demand ratio vs. Ideal demand ratio
    determines + or - to length of fire on time,
    adjustment from previous hour calculated
    fire time.
   Actual demand ratio = 70
   Ideal Demand ratio = .60
   (.70-.60)=.10 x 10= 1 time change factor
   Time increment factor= 2 minutes
   Previous hr. fire time 30 minutes
   1 time chg.. factor x 2 min = +2 min
   Prev. fire time 30min + 2 min= 32 min
   New Burner fire time 32 min (increase)
Annual service is required for all boilers and
furnaces.

Flame check Excess air, Carbon Monoxide,
Good distribution, safety controls, Ware from
corrosion, chimney condition, fuel supply,
filters for fuel and air, Exhaust gases, water
quality, air in piping, venting of air, water
pressure,

Safety checks
efficiency and comfort.
Carbon Monoxide Poisoning

Gas boilers and oil fired boilers and
furnaces ???

It’s the law !!

Why?
         Blood Chemistry
Odorless, colorless,
Source: improper chimney vent of exhaust.
Harm: CO attaches to red blood cells and are
not recognized by our respiratory system. We
cannot use them in the cells. They never leave
the red cell and we starve from lack of oxygen.
Cure: Hospitalization immediately.
Prevention: Annual heating system service.
Carbon monoxide detectors. Replace every five
years.
   Boiler water level. 1/3-1/2 water in fill
    glass
   Pressure monitoring .5-2.0 lbs
   Blow down auto refill devices to remove rust
   Watch it cycle for a full two firings to verify
    pressuretrol safety operation. Check for
    short cycling.
   Check for continuous boiler firing. (longer
    than 40 minutes) This means you need to
    talk to your boiler service to explain.
   Check that all radiation is getting steam.
   Steam is delivered as soon as it is generated.
    Traveling at great speed it will satisfy BTU
    demand quickly. It is most important that all
    system components are in good working order
    as designed. It can not be overemphasized,
    that complete inspection service and repair
    maintenance be done, annually by a
    professional.
   Steam radiators heat and cool quickly.
   A steady radiation of BTU is the ideal.
   How do we do this evenly.
   By controlling the pressure to the need of the
    room.
   WE control the pressure by cycling the boiler
    to put BTU’s in for BTU’s needed.
   Some times the radiator may be hot but only
    half way across.
   Boiler firing rate and oil nozzle size must be
    proper for the boiler to have efficient heat
    exchange from the fire to the waterside. If
    the nozzle is too small the boiler will take
    forever to heat. Steam pressure should be
    met in less than 30 minutes. If not have the
    boiler fire size checked by a professional
    boiler person. See manufacturers suggested
    gallons / hour. This information can be
    found at manufacturers website.
   Many systems have had the asbestos
    insulation removed. Few replace the
    insulation due to the added expense. With
    fuel prices going up, insulation return on
    investment is becoming very attractive. The
    system was designed to work with insulated
    pipes.
   Most steam systems can be reinsulated for
    5-10 dollars per pipe foot.
   You are wasting the heat in the pipes if you
    do not.
   Proper boiler piping measurement check.
   Testing cleaning and repair of:
     air vents, traps, safety controls, chimney
    inspection, flue gas analysis, heat exchange
    cleaning, make up water supply rate, piping
    insulation, condensate return systems and
    boiler water, fuel supply and storage.
   Proper venting of boiler room for fresh air
    and fire prevention.
   Carbon Monoxide detectors are required.
   Out door temperature changes take hours
    before being reflected in interior heat loss.
    Boiler is on before it is needed.

   This causes uneven over heating, and
    open windows.

    Indoor thermostat sensor takes all heat
    loss into consideration from the occupied
    space, where the people are. No wasted
    heat.
                                           Time lag and lead with outdoor reset
  Fixed curve
outdoor temp
                                             noon
                   Exqheat                                              Lag boiler undertemp                                       Lead
                         Real Time curve                                                                                         boiler overheat
                                                          Fixed curve
        Lead                                                                                                      outdoor temp
      boile r overheat                                     outdoor temp
                                                                                                              Fixed curve
                                  area of discomfort                           Exqheat
                                                                                    Real Tim e curve                                Exqheat
                               Comfort Control is First                          Lag boile r underte mp                             Real Time curve



                                                                                                          Night
         Fire time adjusts to satisfy Ideal Demand rate
    80                                                            7 min
    70                                                            6 min




                                                                          adjustmen t
                        X               X         X
  60%     o
          X           o o           o           o
                                                X o           o
    50            X                                       X       5 min
    40                          X                                 4 min
    30                                                            3 min
IDR %         1       2     3       4       5    6    7       8

                            Time in hours
 Steam    heat now has the
    opportunity to be
    comfortable and efficient
    with the intelligent
    management offered by
    Exquisite Heat control.
   www.Exqheat.com 914-588-4791
   John Cockerill US Patent: 6,402,043

				
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posted:9/2/2011
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