The Garage Door Balance Test You Can Run Yourself
What Balance Actually Means
The springs on a garage door are counterweights. When they are correctly tensioned, the door weighs almost nothing at any point in its travel and will stay wherever you put it. Balance is a measure of how well that is still true. It is upstream of nearly everything else, because an unbalanced door overloads its rollers, its hinges, its track and its opener simultaneously.
Before You Start
Do this with the door fully closed and the garage clear of people and vehicles. You are going to disconnect the opener, so make sure nobody is going to press a remote while you are underneath. If a spring is visibly broken, showing a clear gap in the coil, stop here: the test is not safe or meaningful on a door with a failed spring, and the door should not be operated at all.
Step One: Disconnect
With the door closed, pull the emergency release cord on the opener trolley. This detaches the door from the opener so you are testing the door alone. The cord is usually red and hangs from the rail.
Step Two: Lift
Lift the door by hand using the lifting handle or the bottom edge, keeping fingers away from between the sections. It should require a firm but comfortable effort, roughly the weight of a heavy suitcase, and it should feel the same throughout the travel rather than getting suddenly heavier or lighter.
Step Three: Release and Watch
Stop at about waist height and let go, then repeat at about shoulder height. Watch what the door does over the next few seconds. That behaviour is the result.
Reading the Result
If it holds position at both heights, the springs are doing their job and the door is balanced. If it drifts or falls, the springs have lost tension, which is normal with age and is the most common outcome on a door more than six or seven years old. If it rises on its own, the springs are overwound, which puts the door under more force than it should carry and makes the closing cycle harsher. If it holds at one height but not the other, tension is uneven side to side or the door is binding somewhere, and that usually points at track or roller trouble rather than springs.
The Other Thing the Test Tells You
Pay attention to how the door feels rather than only where it stops. Grinding, catching at a particular height, or a sudden change in effort at one point are all mechanical faults you have just isolated from the opener entirely. That is valuable information, and it is why this test is worth running even on a door that turns out to be perfectly balanced.
Step Four: Reconnect Properly
Close the door fully, then pull the release cord again or run the opener, depending on the model, until the trolley re engages with an audible click. Cycle the door once with the opener and confirm it opens and closes normally. Leaving the trolley disengaged means the door is unlocked and free to be lifted by hand from outside.
What Not to Do About a Bad Result
Do not adjust the springs. Torsion springs are wound under very high tension and are adjusted with winding bars by someone who has done it before; the improvised alternatives are how people are seriously hurt. A failed balance test is a call to make, not a job to attempt. Run it twice a year, in spring and autumn, and the springs will almost always be replaced on a schedule rather than on the morning they break.