BOILER START-UP
20
6.4.
Combustion regulation
The flame from the burner must be thin and longitudinal and should not reach the side walls of
the fire chamber (nozzle projection angle=60º, possibly 45º for power over 140 Mcal/h).
The loading of the boiler with an atomizer smaller than the one that corresponds to the normal
heat value supply of the boiler is not recommended. The function of ENDS boilers is possible
up to 70% of their nominal heating output without any significant reduction on the outlet
temperature of the exhaust gases. Output below 70% is not allowed, since there may be
caused harmful corrosions due formation of condensations.
If during the performance measurements the temperature of exhaust gases is too low, there is
the possibility of increasing the by removing two or more turbinators (as required) from the
fire tubes that are placed at the bottom of the front tube plate.
During the combustion regulation of the burner on ENDS boiler type the following values must
be reached:
▪
Burning of light oil: CO2= 12-13%, maximum temperature of burned gases outlet=220ºC
up to 180 kW and for boilers of bigger size 240ºC, soot rate=0-1 Bacharach.
▪
Gas burning: CO2 max=10-12 %, maximum temperature of burned gases outlet=240ºC
▪
Burning of heavy crude oil: temperature of burned gases outlet 220-260ºC, soot rate=0-1
Bacharach.
The measurements are carried out after the temperature of the water of the boiler has been
increased to 80-90ºC. For built chimneys the temperature of burned gases outlet must be at
least 150-170ºC.
GENERAL SUGGESTIONS:
▪
CO: This indicates the excess air supply for good quality combustion. The more the air
increases, the CO% value reduces and the more the air reduces the CO% value increases.
▪
SOOT RATE (according to Bacharach): This number indicates that in the exhaust gases
there are solid particles. If this number exceeds 2 on BH scale, you should check the
atomizer for possible defects or unsuitability for the burner and the boiler (make, type, and
diffusion angle). Generally, the BH number reduces by increasing the pressure of the valve.
In this case you should be careful because the fuel supply increases.
▪
TEMPERATURE OF EXHAUST GASES: This is a value that expresses the heat losses through
the chimney to the environment. The higher the temperature is, the greater the heat loss is
and therefore the lower the efficiency.
NOTE:
The current regulations of each country may require different adjustments from those
that have already been done and this requires observance of other parameters.
