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Power Boiler Q&A |
Savings Proposal |
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Atmospheric Boilers
Four Questions to ask a Heating Expert... |
When analyzing combustion gases,
what indicates increased combustion efficiency?
(better fuel burn) |
| Answer: The fuel is
burning better is there is an increase in the percentage of CO2 (carbon
dioxide) produced by the combustion process. This is the same as a
decrease in the percentage of O2 (oxygen) in the combustion gases. If
CO2 (carbon monoxide) is present, a reduction in the PPM (parts per
million) also indicates a better burn. |
What indicates an increase in
thermal efficiency?
(more available heat is being retained and put to use) |
| Answer: Answer: When the
" stack loss" is reduced there is a corresponding increase in
the retained available heat. Stack loss can be measured for general
comparison by multiplying the net stack temperature by the stack gas
velocity in feet per minute under near identical conditions. |
| Example: A furnace or
boiler is operating in a room with a ambient temperature of 70°F. An
initial stack reading is made of 370° F stack temperature and a draft
of 200 FPM. After some energy-saving modifications were made the stack
reading was 470° and a draft of 100 FPM. What is the change in stack
loss? The net temperature of 300° times 200 FPM equals 60,000 degree
FPM loss. The later reading of 400° multiplied by 100 FPM equals 40,000
degree FPM. The later reading indicates a 33% reduction in stack loss. |
| How can "ideal draft" be
verified in heating equipment? |
| Answer: You know you have
attained "ideal draft" when no combustion gases are spilling
(flowing into area surrounding the heating equipment), but the draft is
as low in velocity as possible while providing adequate combustion air
to the fuel. |
| If all else remains constant, and
one or more of the above factors is improved, is it certain that there
must be an improvement in the overall efficiency of the heating
equipment, resulting in a lowering of the amount of fuel used per unit
of heat/steam produced/used? |
| Answer: Yes. It is certain
that there must be an improvement in overall efficiency. |
