A Toilet That Will Not Flush

Lift the lid. If the tank is empty or barely covered, the problem is supply, not flushing. Check that the shut-off valve behind the toilet is open, and that the fill valve is running when you flush. A tank that will not fill is a supply or fill valve fault and the flush mechanism is fine.

The handle lifts a chain that lifts the flapper. Chains come off, and the plastic arm they hook to breaks — it is the single commonest cause of a handle that moves freely and does nothing. Both are visible the moment the lid is off.

A chain with too much slack gives the other version: the handle moves, the flapper lifts slightly, and the flush is feeble rather than absent. That is a weak flush, which has its own causes.

Then water is reaching the bowl and not leaving it, and the blockage is downstream. A bowl that fills and drains slowly, or fills and rises, is a clog in the trap or the branch — not a fault in the toilet.

The distinction matters because it changes who you need. A blocked line is drain work; a broken flush mechanism is fixture work.

If the bowl rises toward the rim, turn the shut-off valve behind the toilet clockwise until it stops, and do not flush again to see what happens. A second flush against a blockage is how a slow clog becomes water on the floor.

If more than one fixture in the house is slow at the same time — a bath backing up when the toilet flushes, for instance — the blockage is in the main line rather than this fixture, and that is a different call.