Oil vs Propane

A homeowner in northwestern Connecticut, living in a circa-1800s house of about 2,500 square feet, is weighing a heating decision many older-home owners eventually face. Their 14-year-old oil furnace still works, but the oil tanks are 30 years old and need replacing. That raises the question: replace the aging tanks and stick with oil, or replace the furnace itself and switch to propane.

The house has had some upgrades already — insulation in various rooms and the attic, plus new double-pane windows — but the homeowner describes it as still drafty in spots. Regardless of the oil-versus-propane choice, they plan to add a whole-house air-source heat pump (a system that pulls heat from outside air rather than burning fuel) this year, to use during the mild shoulder seasons of fall and spring. The oil or propane furnace would remain the main heat source through the coldest winter months. A ground-mounted solar electric system installed last year, sized at 8.715 kilowatts, is meant to offset the added electric costs from running the heat pump.

The question was posted to a building-science forum without a settled answer yet. For homeowners in similar older houses with aging fuel tanks, it's a useful reminder that a tank or furnace replacement can be a natural moment to reconsider fuel type and add supplemental electric heating, rather than simply swapping in the same equipment.