Springs · Centre Wellington
Extension Spring Replacement
The opener groans on the way up and the door slams the last foot on the way down, hard enough to rattle the windows.
In plain words
Extension springs are common on the detached garages behind older houses, where a low ceiling left no room for a torsion shaft, and those garages are rarely heated. Damp summers, hard frosts and salt carried in on the car pit the spring wire over the years, and a fatigued spring most often lets go on a cold morning when the steel is stiffest. Replacement fits a new pair rated for the door, renews the pulleys and cables that have rusted alongside them, adds containment cables where the original installation never had any, and leaves a door that lifts easily by hand when the power is out.
How the visit goesOpen the door by hand and it drifts back down on its own, a little at first and then all at once. Nothing is broken that you can see, but the springs along the tracks look tired, rusty and slightly sagging.
Extension Spring Replacement
How the visit goes
Weighing the door
Extension springs are chosen by the weight they are built to lift, so the door is weighed rather than guessed at. With the opener released and the springs disconnected or slack, the technician lowers the door onto a scale set on the floor under the bottom section and reads the figure. That number, together with the door's height, sets the spring rating and stretch length. The old springs are measured as a cross-check, but the scale wins if the two disagree, because a door can gain weight from new panels, insulation or a cladding added since the springs went on.
Threading the containment cables
Before a spring is hung, a containment cable is fed through the centre of its coil. One end is anchored at the rear, to the hanger or the framing behind it, and the other is run forward past the pulley and fixed to the bracket at the front of the track or to the wall, with enough slack that the cable never carries load while the spring works. The cable is checked to be clear of the pulley wheel and the lift cable so nothing rubs. Both sides are done the same way, whether or not the old installation had them. A spring that breaks in future is held on the cable rather than crossing the garage.
Knowing when the next set is due
A standard extension spring is made for a set number of open-and-close cycles, commonly in the ten-thousand range, which on a door used four times a day works out to several years and on a door used twice a week to much longer. Springs age even when idle, as rust does its slow work in an unheated garage. The signs that the set is nearing the end are gradual: the door feels heavier by hand, the opener sounds as if it is working, the door drifts down from halfway, and gaps appear between coils when the door is open. Acting on those signs turns the next replacement into a planned appointment rather than a bang in the night.
Extension Spring Replacement
In the van
Containment (safety) cables
Lag screws and hanger bolts
Bottom brackets and clevis pins
Track clamps or locking pliers
Lift cables
Extension Spring Replacement
What affects the quote
Getting the van to the garage
A detached garage down a shared laneway, a rural property or a building with the bay behind a gate takes more time to reach and set up in, and the quote allows for that.
Working room around the springs
Shelving, a stored canoe or a car parked under the tracks slows the work along the horizontal run. Clearing the sides of the garage beforehand keeps the time on the quote short.
How the door is sitting
A door resting closed with one spring gone is straightforward. A door stuck partway, twisted in its tracks or with a cable wrapped around a pulley has to be supported and straightened first.
What to have ready
- Does one corner of the door hang lower than the other?
- Does the opener still move the door, and does it sound strained?
- Is a spring broken in two, hanging loose, or just looking stretched?
Extension Spring Replacement: questions
QuestionsWhy does the opener get adjusted after new springs?
Because the door is now much lighter for the opener to move. Over the years, as the old springs weakened, the opener's force setting may have been turned up to keep the door going, and its travel limits were set against a door that sat differently on the floor. Left alone, that extra force would push the newly balanced door too hard. Resetting force and travel, then repeating the reversal tests, matches the opener to the door it now has.
Should I try to open the door by hand before the technician arrives?
No need, and it is easier on the door if you leave it. With a spring broken or slack, the door is unbalanced and heavy, and lifting it can let it drop or twist a section in the track. If the door is stuck partway, leave it there and keep people and the car away from the opening. The technician brings clamps and props, and the door is secured before it is moved at all.
My springs squeak and twang. Is that normal?
Some noise is ordinary. Extension springs stretch and relax on every trip, and a dry coil or a pulley with a dry axle will squeak, especially in cold weather; a light spray of lubricant along the springs and a drop on each pulley usually quiets it. A sharper twang, or a new grinding from a pulley, is worth a look, since a stiff pulley loads the spring and wears the cable.
