Trap primer

Plumbing · Introduction · printed page 285 (PDF page 286)

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Plumbing

Text in the illustration

the trap primer is typically a 3/8" diameter plastic tube attached to a fixture (e.g. laundry tub)
whenever the fixture is used, some water is sent to the floor drain trap to keep it filled
the trap primer is often fed into a piece of polyethylene pipe when it must pass through a concrete floor
trap primer
cross section
floor drain
foundation wall
waste stack
faucet
trap seal
laundry tub
loose fit
air gap
polyethylene pipe (extension of trap primer)

Generated explanation

The illustration shows a laundry-tub faucet supplying a trap-primer tube that delivers water to a floor-drain trap beneath a concrete floor. The primer tube feeds into a polyethylene pipe extension, with an enlarged detail identifying a loose fit and air gap at the connection. A second enlarged cross section shows water dripping from the primer into the floor drain and maintaining the trap seal. The surrounding assembly includes the foundation wall, waste stack, laundry-tub drain, and below-floor drainage piping. The annotations explain that fixture use replenishes the floor-drain trap.

Components

trap primer trap-primer tube polyethylene pipe extension floor drain floor-drain trap trap seal laundry tub faucet laundry-tub drain trap waste stack below-floor drainage piping concrete floor foundation wall

Materials

plastic tubing polyethylene pipe concrete granular aggregate

Related illustrations

1644

Trap primer

· p. 290

The illustration shows a laundry tub faucet supplying a small plastic trap-primer tube that delivers water to a floor drain trap. The tube connects to a polyethylene pipe extension routed through the concrete floor to th