Well if ou know what you are getting for home heating oil then you are ok the problem is they can substitute many different grades for HHO.
Home Heating Oil / Fuel Oil #4 and Home Heating Oil / Fuel Oil #6 have a higher BTU content. This is normally accomplished by adding much heavier petroleum oil distillate similar to automotive motor oil to the formulation. This allows a furnace to burn less fuel, for each BTU of heat produced, as well as often times reducing the cost per gallon of fuel. These types of Home Heating Oil / Fuel Oil should NOT be used in a Diesel Fueled Engine or Generator.
In times of shortage, Standard Road Diesel #2, Diesel #1, Kerosene, K-1, Jet Fuel, JP-1, Agricultural Diesel, Diesel #2, Home Heating Oil / Fuel Oil #4, or Home Heating Oil / Fuel Oil #6 may be shipped by fuel distribution companies and sold for use as home heating oil. There may also be times that, due to economic and other considerations, fuel distributors sell any or all of these products, or combinations and blends of the same, to home owners, as simply Home Heating Oil / Fuel Oil.
SUMMARY: Home Heating Oil / Fuel Oil #2 and Off Road / Agricultural Diesel #2 seem to be very similar products. More importantly, Home Heating Oil #2 is refers to a very specific product, and a very specific formulation, which, in many cases, may be a very similar product in terms of composition and formulation as Off-Road Agricultural Grade Diesel #2.
Take a chance with your nice new tractor if you like
Frank