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Hartford and Ratliff Co. has certified technicians to take care of your AC installation near Novi MI.
Hartford & Ratliff Co., Inc.
The Original Hot Water Specialists Since 1955

(248) 471-3110
For Parts: (800) 466-3110
Hartford and Ratliff Co. has been a trusted Air Conditioning contractor in Farmington MI since 1955.
Hartford & Ratliff Co., Inc.
For Parts: (800) 466-3110

Understanding Basic Combustion

There's more to a Tune-up than a quick "Once-Over"...

Understanding Basic Combustion


Useful Information on Combustion Efficient Fuel Use

A Definition:

Combustion is the rapid oxidation of a fuel resulting in the release of usable heat and the production of a visible flame

The Combustion Equation:

Natural Gas With Air:

CH4 + 2O2 + 8N2 ----------->

CO2 + 2H2O + 8N2 + 1000 BTU Heat

Examples of Combustion

Perfect Combustion Provides:

The hottest flame
Minimum exhaust volume

Perfect Combustion

Characteristics:

  • All fuel combusted
  • Blue near burner tile
  • Forms a yellow conical flame shape
  • Produces the highest flame temperature
  • Provides the minimum exhaust volume

Lean Combustion

Characteristics:

  • Flue products oxidizing (Free O2)
  • Pale blue color
  • Forms a more conical flame
  • All fuel combusted
  • Flame temperature drops (Heating excess air)

Incomplete Combustion

Characteristics:

  • Air starved or fuel rich
  • Carbon Monoxide and H2 formed
  • Reducing atmosphere
  • Flame color is predominantly yellow color
  • The flame is less defined
  • Flame temperature drops

Optimum Energy Utilization Occurs When Perfect Combustion Ratios Are Maintained

When A Furnace Tune-Up Is Done Right The Technician will have taken time to:

  • Verify proper mix and directed air/fuel supply
  • Confirm that you have stable combustion
  • Check to make sure that the system is venting all the by-products of the exhaust flue gases

A Definition of Combustion Terms

Excess Air Definition:

Air remaining after the fuel has been combusted
-or-
Air supplied in addition to the quantity needed for stoichiometric combustion

Primary & Secondary Air:

Primary Air --

  • Air mixed with the fuel prior to ignition

Secondary Air --

  • Air supplied to the flame after it is ignited

Secondary Air Effects --

  • Imprecise air/fuel ratio control
  • Exhaust volume increases
  • Fuel rate rises
  • Less available heat
24 Hour Emergency Service  •  Call Us Today  •  (248) 471-3110  •  or  •  Schedule Service Online
24 Hour Emergency Service
(248) 471-3110
Schedule Service Online
We service most AC brands and models near Farmington MI.
Hartford & Ratliff Co., Inc.
Farmington, MI 48336
Phone: (248) 471-3110
Toll Free: (800) 466-3110
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