Oil Storage and Fuel Delivery
This domain tests how oil is stored, vented, and delivered to the burner. Expect tank types and supports, fill and vent piping, gauges and whistles, supply-line arrangements, filters, and the safety rules that prevent spills and air lock.
Tanks and piping
- Common tanks are 275-gal oval, 330-gal, and 550/1,000-gal horizontal; tanks need solid supports, clearance for inspection, and protection from vehicle damage.
- Fill pipe is typically 2 in. and the vent at least 1¼ in.; the vent must terminate outside, above the expected snow line, with a weatherproof cap and no screen that can clog.
- A vent whistle sounds as the tank fills; it is a warning, not a gauge. The tank gauge and delivery ticket remain the reliable level check.
- Supply lines are single-pipe gravity feed or two-pipe with a return. A two-pipe pump needs its bypass plug removed; a single-pipe system must not be asked to lift oil.
Filters and safety
- A filter and shutoff valve belong at the tank outlet; a fusible-link or fire valve protects the line. Lines must be protected from traffic and frost and sloped to avoid air pockets.
Worked example
A 275-gal tank reads half full - about 137 gal. A 1.0 gph burner at 40% duty cycle averages 0.40 gph, or 9.6 gal/day. 137 ÷ 9.6 ≈ 14 days of operation before the tank is near empty. That is why a gauge reading alone is not a delivery plan: the low-level cutoff and suction line can lose prime before the tank is truly empty.
Traps
- Plugging a vent to stop a whistle causes pressure and spills.
- A stuck gauge can read full when the tank is empty.
- A two-pipe pump without its bypass plug will not build pressure.
- An unprotected buried line can be crushed or fill with water.