air handler stays running

[ruger300]

my air handler stays running after temp is reached. my heat pump cycle as it needs to. i have changed the contacts in air handler it still does same. i also put in a new digital therosat. it still stays on. my unit is a trane.

[hvacwiz]

You either have a fan reley sticking or a sequencer that controls the electric heat strips/fan sticking

[ruger300]

where would that fan relay be located at on the air handler or heat pump. thanhs for advice

[hvacwiz]

It would be in the air handler, look at your wiring diagram for your indoor unit on the back of the door maybe, find your fan motor and see where the wires go to, should lead you right to the problem.