Hi wil,
its about 33 years old. had it overhauled 2 years ago.
Just did a google & found this:
Typical costs:
Replacing an old oil-fired furnace with a new one typically costs $2,000-$5,000 for a simple installation of a basic model, but it can cost $6,000-$10,000 or more for a larger, more energy-efficient unit with a difficult installation, such as a complex floor plan or hard-to-reach ductwork. For example, the Carrier Comfort 80 Oil Furnace[1] series with 70,000-154,000 BTU and an AFUE rating (the amount of fuel converted into usable heat) of up to 82.4% is advertised as an economic choice, while the Carrier Performance OVL/OVM Oil Furnace[2] series with 77,000-154,000 BTU and an AFUE rating of up to 86.6% is advertised as providing added comfort and higher efficiency.
Oil-fuel furnaces are usually sold through a contractor with installation included in the pricing, and manufacturers do not typically publish suggested retail prices.
http://home.costhelper.com/oil-furnace.html

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