Broken torsion spring
A single bang, and then a door that will not lift. It is the most common emergency in this trade and the one with the worst do-it-yourself accident record.
Do not lift the door. Do not run the opener. Do not touch the spring or the winding cones. The door's whole weight is now hanging on two cables that have just taken a shock load, and the shaft above it is still under tension.
Look at the shaft above the opening. A broken torsion spring has a clean two-inch gap in the coil, as though somebody cut a slice out of it. Often there was a single loud bang, sometimes in the night, and the door was fine until somebody pressed the button the next morning. The opener will strain, hum, or move the door a few inches and give up.
What has actually happened
A torsion spring does not lift your door. It counterbalances it. When the door is down, the spring is wound tight and holding almost the entire weight of the door as stored energy. As the door rises, the spring unwinds and hands that energy back. Done properly, a 180-pound door feels like eight or ten pounds in your hands the whole way up.
When the spring breaks, that counterbalance vanishes instantly. The door now weighs everything it weighs. Two thin steel cables and a half-horsepower opener are all that is between it and the floor, and neither is designed for the job. This is why the advice above is not caution for the sake of it: people are hurt every year lifting a door with a broken spring, and people are hurt every year trying to wind a new one in without bars.
Why we will not talk you through it
Winding a torsion spring means putting a solid steel bar into a hole in the winding cone, taking the load, and turning the cone through a precise number of quarter turns while moving the second bar into the next hole. The bars must be the right diameter for the cone and long enough to give control. Screwdrivers slip. Rebar bends. A socket extension will fold and let the cone go, and when a cone goes it unwinds through whatever is in front of it.
There is no version of this conversation on the phone that ends well, so we do not have it. If we cannot get to you soon enough, we will say so and you can call somebody else — just ask them whether they own winding bars, and take the answer seriously.
One spring or two
Some doors have a single spring, some have a pair. If a door was built with two and one has gone, the other is the same age and has done the same number of cycles. It is very often within months of going itself. We will tell you the price for one and for both, and we will not pretend the second one is urgent if it is genuinely new — but on a matched pair fitted at the same time, changing only one is usually false economy, and if that is what you choose it goes on the ticket so nobody is surprised later.
What gets replaced with it
A spring rarely breaks quietly. When it lets go, the door drops until the cables catch, and that shock goes straight into the cables, the drums and the bottom brackets. So before we quote a total we look at all three.
Cables
A cable that has taken a shock often has a strand or two that has started to lift — you can see it bird-caging away from the lay of the wire. That cable will fail, and it is a fraction of the price of the spring.
Drums
If the cables jumped their grooves when the door dropped, the drums need re-seating and setting to the same mark on both sides so the door comes up square. A drum that has been chewed by a loose cable gets replaced.
Bearings and the shaft
The center bearing plate and the two end bearings turn every cycle for years and are cheap. If one is dry or notchy while the shaft is already coming apart, it goes in.
What goes in
Unless you tell us otherwise, a 25,000-cycle spring in place of the 10,000-cycle part that usually comes out. On a door opened four times a day that is roughly sixteen years instead of seven. The wire size, inside diameter, length, wind direction and rating go on your ticket.
Then the door is balanced by hand with the opener disconnected. It should hold at waist height. A spring wound to the wrong number of turns is the most common reason a brand new spring feels wrong, and it is the last thing checked before the opener goes back on.
The two-minute test that comes first
- releasedThe trolley is disconnected at the cord, so the door is off the opener.
- stays putBalanced. This is the one you want.
- runs upOver-wound.
- dropsThe spring is weak or wrongly sized.
Balance, opener disconnected
Not on a door with a broken spring — with a gap in the coil the door weighs everything it weighs. On every other door this is where we start, because a door that will not hold its own height is a spring problem however the opener is behaving.
What it costs
- Attend and diagnose
- $89.00, including the balance test and both safety tests whether or not you proceed.
- Single torsion spring
- $260 – $340 fitted, high-cycle, including balancing the door and re-testing. The range is wire size and length, not a negotiation.
- Pair of springs
- $420 – $540 fitted. Cheaper than two separate visits, which is why we ask about the second one now rather than in eight months.
- Cables, if damaged
- $70 – $95 for the pair, fitted at the same time.
- Same-day
- No surcharge. A broken spring that trapped a car goes to the front of the day because it should, not because it pays more.
Example figures on a demonstration site. They are the shape of real pricing — a call-out plus parts — not a quote from anybody.