Lamps fail in a predictable order. After a few years of ordinary use, the same handful of components give up, and none of them is the lamp itself. Knowing the sequence tells you what to keep in the cupboard and stops a working lamp being thrown out because one cheap part has worn.

First: the wick

Cotton wick is a consumable and behaves like one. It shortens with every trim, stiffens with residue low down, and eventually draws fuel unevenly no matter how neatly you cut it. Expect to replace it periodically depending on use, and keep a spare in the correct width so the change takes two minutes rather than a fortnight of waiting.

Second: the chimney

Glass breaks, and it usually breaks from thermal shock or a knock during cleaning rather than in use. Replacements are matched by base diameter and height, so measure before ordering; a supplier that lists chimneys by size alongside wicks and burners, such as https://lamplight.us.org/, is worth more here than a general shop, because a nearly-right chimney makes a good lamp smoke.

Third: the wick-raising mechanism

The little toothed wheel that lifts the wick collects carbon and grit, and after a few seasons it slips, jams or turns without moving anything. Sometimes a strip-down and clean of a cold lamp restores it. When it does not, the whole burner is the replacement unit, and burners are made to standard thread sizes.

Fourth: seals and the filler cap

Gaskets and cap washers perish, and a lamp that used to hold fuel starts leaving a faint ring on the table. This one matters: leaking fuel under a burning lamp is the fault most worth catching early. Check by standing a filled lamp on paper for a few hours before you trust it.

What to keep in stock

• Two spare wicks of the correct width.
• One spare chimney, wrapped, stored upright.
• A spare burner if the lamp is your emergency light.
• A sealed bottle of refined fuel, checked annually.
• A soft brush and lint-free cloths kept with the lamp.

What almost never fails

The fount and the base, on a modern lamp, will outlast everything else by decades. That is why replacing the consumables is nearly always the right call, and why buying a new lamp because it smokes is usually a waste. Match the parts to the lamp you have rather than starting again.

The failures that end a lamp

A cracked or holed fount, a base that no longer sits flat, a burner thread stripped beyond repair, or a fitting in a size nobody manufactures. Any of these turns a lamp into a decorative object, and there is no shame in accepting that. What you must not do is keep burning a lamp that leaks or wobbles because the parts are inconvenient to find.

A five-minute seasonal service

Once a year, on a cold, empty lamp: remove the burner, brush the air holes, check the wick and the raising wheel, inspect the chimney against the light, wipe the fount and check underneath for damp. Then refill, set the flame low and watch it for ten minutes before you rely on it in a power cut.