Garage Doors in Silverthorne, OntarioRollers, hingesand the small parts.

Yes, and in winter it is one of the most common causes. Meltwater under the bottom seal refreezes overnight and bonds the door to the slab. The opener pulls, the door stays put, the cables go slack and unwind off their drums, and when the ice lets go the door lurches up unevenly. Freeing the seal by hand before using the opener on icy mornings prevents almost all of these calls.

Three things. Spray the springs, pulley axles and hinges with a garage-door lubricant twice a year, which slows rust in an unheated garage. Keep the threshold clear of bins and packed snow so the door never stops short with the springs still pulling. And leave the opener's force setting where the technician put it, since a door that starts needing more push is a balance question rather than a dial to turn.

With the door closed, the opener is released so the door is free. It is lifted by hand to about a metre, then to fully open, and let go at each point. A door in balance holds its position; one that rises on its own is over-tensioned and one that drops is under-tensioned. The door should also move freely and no faster than the hand pushing it.

Park the cars outside and leave the floor beneath the rail and the door's path open so a stepladder can be set at either end. Lift bicycles and boxes off hooks near the rail. Keep the remotes and wall control within reach and know where the operator plugs in. If the door is stuck closed with a car inside, mention it when booking.

Sensors and head unit are made for each other; a board reads its own maker's sensors, often a particular generation of them, so the pair in the box is what goes on the wall and the old ones come down with the old opener. The new pair sits low at each side of the doorway, roughly a hand's width above the concrete, and the technician confirms their indicator lights are steady before the door is tested against the beam.