​Not sure how much oil is  left in that tank?


A standard residential oil tank holds 275 gallons. Based on that size, the following readings indicate that your tank contains approximately this many gallons:
1/8 = 40 gals
1/4 = 70 gals
3/8 = 100 gals
1/2 = 130 gals
5/8 = 160 gals
3/4 = 200 gals
7/8 = 240 gals
“full” = 265 gals

​I just filled my tank- how long will it last me?
How long a tank of heating oil will last depends on the following variables:

The size of the oil tank - since oil tanks are often oval in cross section or round, the oil tank gauge is not precise, and it is giving the accurate reading of how much oil is in the tank only at 3 points: when the oil tank is full, half full, and empty.

The setting of the room thermostat - setting to a higher temperature makes a big increase in the rate at which heating oil will be consumed.

The outdoor temperature - colder outside temperatures increase the rate of heating oil consumption. Because outdoor temperature varies widely during the day and season, oil companies use a better measurement, heating degree days (HDD), that describes the heating load that your heating system will have to meet.  Heating degree days or HDD are defined using a base temperature at which it is assumed that no heat would be required, typically 65 degF.  

Outdoor wind conditions - wind significantly increases the rate of heat loss from a building, depending on building insulation and draftiness.

Building insulation level - how well the building is insulated is a major factor in determining its rate of heat loss and thus its rate of heating fuel consumption.

Building air tightness - a drafty building loses heat significantly faster than a tight building, even if the drafty building is "insulated".

Oil burner nozzle size in GPH (gallons per hour) of oil delivery - oil burner nozzles deliver oil into the oil burner combustion chamber. Every oil fired heating appliance includes a data plate that includes the range of oil burner nozzle sizes or flow rates that will work properly for that appliance. Typically residential heating oil burner nozzles deliver oil at rates from .65 gph for a small or highly efficient system to 2 gph for an older or larger capacity (in BTUs) heating appliance.

Heating system efficiency numbers can be defined as the portion of each dollar that you spend on heat actually delivers heat into the building as opposed to sending it up the chimney or flue. A heating system that is 85% efficient means that for every dollar that you spend on heating fuel, 85 cents of that dollar sends heat into the building and 15 cents of that dollar goes up the chimney as waste.

Make a Rough Guess at How Long the Oil Tank Will Last

You can make a very rough guess by noting how many minutes per hour or day your oil burner is running.  Typically on a home, around .8 to 1.7 gallons per hour. Of course this varies widely for the reasons outlined above.
Example of Calculation of Days Supply of Heating Oil Remaining in an Oil Storage Tank

G = Gallons of oil remaining the tank

GPH = oil consumption rate when the oil burner is running, in gallons per hour - the largest number on your oil heater's data plate, or the actual GPH number for the oil burner nozzle actually installed on your oil burner (usually this is smaller than the data tag maximum)

MPH = minutes per hour that your oil burner is running, averaged over 24 hours per day, from observation

GPD = (GPH x MPH / 60) = gallons of heating oil used per day

Here is an example using some sample numbers: 100 gallons of oil in the oil tank and a 1 GPM oil burner nozzle.

G=100 gallons of heating oil in the tank

GPH = oil burner nozzle deliver rate in gallons per hour (from data tag on oil heater or number stamped on oil burner nozzle)

MPH = 15 minutes per hour that the oil burner is actually firing (from observation)

15 (minutes of "burner on time" per hour) x 24 (hours in a day) = 360 minutes of burner on time per day
GPD = 1 (GPH) x (360 (burner on time per day) / 60 (minutes per hour)) = 6 gallons of oil used per day.
100 G (gallons of oil in the tank) / 6 (gallons of oil used per day) = 16.6 days of heating oil supply remaining
​How low should I let my tank go before I call in a delivery?
We sugguest when you are between 1/2 and 1/4 - our ideal delivery would be 180 gallons.

If your oil tank is 1/4 full or less and it's during the cold heating season, get a call in as soon as possible. We always try our best to get you as soon as possibe- but it is the customers responsibility to call before they are critically low. Same day deliveries in busy season sometimes cannot be made.  

In an emergency if you are out or almost out of heating oil and we cannot get to you in time with a full tuck delivery, we can send a technician who can bring a 5-gallon container of oil to pour into your heating oil tank (for a service call fee $80-$130 plus fuel) , or you can purchase diesel fuel at a gas station and use that yourself until normal business hours- or next delivery route.

If you run out of heating oil, re-starting the oil burner may require a service call. Sometmes it is necessary to bleed air out of the oil piping in order to properly re-start the oil burner.

We offer automatic delivery- If you are on automatic oil delivery we will have computerized data showing your home's oil consumption rate as a function of "degree days" - a rough measure of how many hours at what outdoor temperature your home is being exposed to winter weather.  When our system alerts us that you may be getting low- we automatically come fill your tank.

​We also offer different options to replace your tank guage.  From standard tank guages that will simply replace what is already there.  To new guages that we can install on your tank and give you a LCD display gauge to put some place easy to view- that alerts you when you get low!

​How can I be sure I never run out? My guage does not work, or I cannot get to it easily.