3/8 inch flare fittings
Brass 45 degree flare nuts, unions, elbows and adapters for 3/8 inch outside diameter copper.
Why it earns its place: 3/8 is the common size at the burner and on short runs.
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Oil line kit
Oil lines are joined with 45 degree flare fittings, never compression fittings. This is the set for a line run or a repair: fittings in both common sizes, the tool that forms the flare, the cutter that makes a square end, the fire valve at the burner, the flex lines that connect it, and the de-aerator that lets a one pipe system bleed itself.
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1/2 inch flare fittings
The same 45 degree family for 1/2 inch outside diameter copper.
Why it earns its place: Longer runs and two pipe systems use 1/2 inch line.
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Flaring tool, 45 degree
Clamps the tube in a bar and spins a cone into the end to form the 45 degree flare that a flare nut seals on.
Why it earns its place: Oil lines are flare, not compression. This is the tool that makes the joint.
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Tubing cutters, 3/4 inch and mini
A wheel cutter for copper oil line. The mini fits where the full size cannot turn.
Why it earns its place: A hacksaw leaves burrs that end up in the nozzle. A square cut is the start of a good flare.
Fusible oil safety valve
A fuel shutoff with a fusible link that closes the oil line automatically in a fire.
Replace it when: It sticks, leaks, or its fusible link has tripped.
Often replaced at the same visit: oil filter, nozzle, pump strainer (in the tune-up kit)
Fusible oil safety valve: how it works and what to buy →
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Flexible oil lines
The flexible flare-ended lines that connect the burner (or a de-aerator) to the rigid oil line, so the burner can be swung open for service without unmaking fittings.
Replace it when: Cracked, stiff, kinked or weeping, and whenever the burner is repiped for a de-aerator.
Often replaced at the same visit: de-aerator
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Fuel oil de-aerator
Purges air from the oil line so a one-pipe system self-bleeds after a run-out instead of locking out on air.
Replace it when: Repeated air-in-line lockouts, especially after the tank has run dry.
Often replaced at the same visit: flex oil lines
Fuel oil de-aerator: how it works and what to buy →
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Oil absorbent pads
A sheet of oil-only sorbent laid under the burner, filter, and pump. It catches the drips from a filter change, a bleed, or a weeping fitting before they soak into the floor and leave the boiler room smelling of oil.
Replace it when: Whenever a pad is saturated or you can smell oil near the burner. Put a fresh one down before a filter change or a bleed, and keep a pack on the shelf.
Other kits
- Nozzle change kit: The nozzle, the wrench, the electrode gauge, the pressure gauge, a filter and pads.
- Pump test kit: Pressure gauge, vacuum gauge, and the adapters that fit the pump ports.
- Combustion test kit: The analyzer, the smoke tester it does not replace, the draft gauge, and a meter.
- The whole bag, by group: tools and gear.
https://oilburnerhelp.com/gear/oil-line/