Whirlpool dryer error codes: most of them are the vent, or one leg of the power.

The dryer measured too little air moving through it. The display prints AF, the Check Vent light comes on, and the cycle runs long or ends early with damp clothes.

1. The lint screen is out, clean, and its slot is clear — reach into the slot with a vacuum crevice tool; lint builds under the screen.
2. The vent hose behind the dryer is not crushed against the wall or kinked, and it is metal, not white vinyl. Pull the dryer out a foot and look.
3. The flap on the outside hood opens when the dryer runs — go outside and feel for air. No air, or a trickle, is a clogged duct in the wall or ceiling.
4. The duct run is short: every 90° elbow counts as 5 feet, and a run over about 35 feet of developed length cannot carry the air.
5. Disconnect the vent hose from the back and run a Timed Dry — if the dryer heats and the code stays gone, the duct is the whole story.

Clean the duct end to end (a dryer vent brush kit from the hardware store, or a vent cleaning service), replace crushed or vinyl hose with rigid or semi-rigid metal, and shorten the run where it can be shortened. A dryer that prints AF with the hose off the back is its own blower wheel or a sensor — a service call.

An electric dryer is getting 120V instead of 240V. The motor runs, the drum turns, and there is no heat — one of the two breakers tripped, or one leg of the outlet is dead.

1. The dryer's breaker in the panel is a double (two handles tied together) and both are fully on. Switch it all the way off and back on; a tripped half does not always look tripped.
2. The dryer is plugged straight into its own 240V outlet, never an extension cord or an adapter.
3. A newly installed cord: the terminal block screws are tight and the strap is right for a 3-prong or a 4-prong cord. A loose terminal on a new cord is the usual L2 on a new dryer.

Reset the breaker and the code clears. A breaker that trips again, a dead leg at the outlet, or a cord to re-terminate is a licensed electrician's job — 240V work is never a home repair. A dryer on a sound outlet that still prints L2 has a fault on its own board — a service call.

Not a fault. The power went out while the dryer was running; the cycle stopped where it was.

1. Press Start to pick the cycle back up, or start a Timed Dry to finish the load.

Nothing to fix. PF with no outage is a plug loose in the outlet or a breaker that is failing — an electrician's look.

Not a fault. The panel is locked so a child cannot start the dryer; the display reads LoC or shows the lock light.

1. Press and hold the button the panel marks Control Lock (on many models Cycle Signal or Wrinkle Shield) for three seconds until the lock light goes out.

The lock turns off and the panel answers again.