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Just wondering about oil tanks

DanHolohan Member, Moderator, Administrator Posts: 15,430
Does anyone know why they chose 275 gallons as the size for most houses?
Retired and loving it.


  • clammy
    clammy Member Posts: 2,668
    oil tank size

    Here's one or two thoughts .Width they always seem to just squeeze through a 28 inch basement door,The other thought is the volume most smaller homes w a 275 usually had a tankless coil and I fiqure that in the off season when just being used for hot water they could maybe get by for about 1 to 1 1/2 months with a delivery.Alot of the oil jobs I used to service had 275 tanks and went at least that long off season but usually got  a oil delivery at least once a month  but a lot of times it would just be a top off.Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • Steamhead
    Steamhead Member Posts: 14,838
    I think Clammy's right

    the oblong shape appears to have been chosen so you could get it thru basement doors, and the length and height so you could get it around corners. The resulting capacity worked out to 275 gallons or, if you could get away with a longer tank (72 rather than 60 inches) 330. 
    All Steamed Up, Inc.
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • SWEI
    SWEI Member Posts: 7,356
    275 and 330

    are both divisible by 55.  Think barrels.  Note these are also the standard sizes of IBCs.
  • Snowmelt
    Snowmelt Member Posts: 1,295

    About Roth oil tanks now that we're on the subject, who here took the Roth training course ( about 2 hours)
  • bob_46
    bob_46 Member Posts: 813
    Golden section

    The golden section / ratio is 1.618 to 1 or rounded 1.62 . The proportions of the end view of the 275 gal oil tank are 44/27 or 1.62 to one. The proportions of the Parthenon are the same. Coincidence ? Great minds .
  • icesailor
    icesailor Member Posts: 7,265
    Diagonal Measurements.

    You always have to take the diagonal measurement into consideration.