Either kerosene or diesel fuel can be purchased at many local gas stations. While these fuels are more expensive than heating oil, both will burn safely in your heating oil burner. Usually 5 or 10 gallons will last for a day or two, depending upon the temperature and the size of your home.Click to see full answer. Keeping this in view, how long will 5 gallons of heating oil last?While these fuels are more expensive than heating oil, both will burn safely in your heating oil burner. Usually 5 or 10 gallons will last for a day or two, depending upon the temperature and the size of your home.Subsequently, question is, how many gallons of heating oil does the average house use per day? The average home uses 5.3 gallons of oil on 30-degree days and 4.5 gallons on 35-degree days. Therefore, the average home in the Philadelphia area will use about 4.9 gallons of heating oil per day during winter. A 275-gallon supply of heating oil will last for approximately 56 days at the rate of 4.9 gallons per day. Also Know, how long will 15 gallons of diesel last in oil tank? When should I fill my oil tank? Average Outside Temperature (°F) Approximate Gallons Used in 24 Hours Approximate Days 25 Gallons Will Last 15 7.8 3.2 20 7.0 3.6 25 6.2 4.0 30 5.3 4.7 How long will 50 gallons of kerosene last? The heating oil chart below uses 25 gallons for easy math. Average Outside Temperature (°F) Approximate Gallons Used in 24 Hours Approximate Days 25 Gallons Will Last 35 4.5 5.6 40 3.7 6.8 45 2.8 8.9 50 2.0 12.5