Pedarrin2:

There are many different grades of fuel oil, ranging from #1 fuel oil (which is essentially a kerosene) to #6 fuel oil which is a heavy (high-boiling point) fuel oil used for maritime bunker oil.

As a very broad generality: diesel oil, #2 fuel oil, distillate fuel oil and homeheating oil are all names for essentially the same product.

Milton Beychok
(Contact me at www.air-dispersion.com)
.

Diesel, while it is all inclusive, more often connotes a term for over-the-road fuel, while #2 fuel oil connotes a fuel to a specific distillation curve.

Over the road fuel basically starts as #2, but is blended and has additives that make it different from a straight run #2 distillate.

It is blended for climatic conditions.  Diesel fuel in the north of the USA may be a significant percentage of #1 in order to give it a higher cloud point.  In the fartherest northern regions "Diesel" might be straight #1.

There are also cetane enhancers added and pour point supressors, and other things blended in by the refinery depending upon the market (winter or summer) that it is going into.

Trucks (that I owned) that came up from the south with fuel blended for that region that got caught in a sudden temperature drop have been known to have had to be towed to an enclosed shop and thawed out and the fuel drained and replaced with fuel suitable for the ambient conditions.

It gets much more technical than that, but those are basics.

In the southern part of our country where I live, the pipelines right now are full of fuel blended for winter conditions on its way to the north for the winter and next spring's planting season.  In the middle of next winter, their summer fuel will be in the pipelines.  In the days before they colored 'off road' diesel to diferentiate it from 'over the road' diesel, certain marketers used to color their product to indicate that it had the winterizing additives.

For those local marketers who pulled their product from the pipelines (as opposed to those who pulled from refineries in the area) you could buy the prettiest red winterized T***** diesel in the middle of the summer here in the deep south.  Ran like crap.  It was too thin.

Buy from them in the winter, and you were lucky to get your vehicle started on the summer fuel that they sold.

None of these issues would matter at all with home heating oil, which is more of the straight #2 cut.

rmw

Fairly similar and equivalent are a country mile apart.

Also note that diesels have additives appropriate for the intended application. Marine diesels, for example, do not have the same lubricants and detergents as road diesels. Sulphur content may be a significant difference. Marine diesels typically can have upto 2.0% sulphur and lubricants to suit.
 
These examples are to suggest that the best approach is to compare the suppliers fuel specifications in all particulars and to ensure that the intended use is one for which they are designed.

Domestic heating fuel is not the most expensive fuel since it has less need for lubricants, detergents etc. so using an alternative for domestic heating is likely to have less problems but greater cost. The alternative, to use domestic heating oil as an engine fuel may bring lower costs but significant problems. This is, of course, best checked by refering to the engine manufacturers recomended fuels. There is a report somewhere on the web which details each engine manufacturer and the allowed fuel grades. I don't recall seeing heating oil among them.

http://www.dieselnet.com/standards/fuels/us.html
http://www.epa.gov/otaq/regs/fuels/diesel/diesel.htm

Web searches should reveal all.

JMW
www.ViscoAnalyser.com

Get a copy of ASTM standards such as D 396 – 04, Standard Specification for Fuel Oils.  ASTM D396 "covers grades of fuel oil intended for use in various types of fuel-oil-burning equipment under various climatic and operating conditions. These grades are described as follows:

Grades 1, (and 1 Low Sulfur,) 2 (and 2 Low Sulfur) are middle distillate fuels for use in domestic and small industrial burners. Grades 1 and 1 Low Sulfur are particularly adapted to vaporizing type burners or where storage conditions require low pour point fuel.  Grade 1 is basically kerosine and grade 2 is basically Diesel fuel oil.

The marine Diesel is less volitile than Diesel.

John