Opener hums but the garage door does not move

Humming opener

What a hum with no movement is telling you

When you press the button and hear the opener hum, click or whir while the door does nothing, you have learned something useful. The opener has power, the logic board is receiving your signal and the motor is trying to turn. What has failed is the connection between that turning motor and the door itself.

That narrows the field. If the opener were dead, you would hear nothing and see no light. A humming motor suggests the electrical side is at least partly working. The trouble is more likely in the chain of parts that turn motor rotation into door travel: the drive gear, the chain, belt or screw, the trolley that connects to the door, and the springs that make the door light enough to lift.

Many homeowners assume the opener has burned out and start shopping for a new one. Often that is not the case. In a large share of these calls the door is simply too heavy for the opener because a spring has broken, and the opener is doing exactly what it should, which is giving up.

This page walks through the four most likely causes, the clues that separate them and the checks that are safe to make. It is general guidance. The only way to know the cause on your own door is an inspection.

One more point before the causes. The hum itself can vary, and the variation is a clue. A steady, low hum that holds for a few seconds and stops often means the motor is straining against a load it cannot move. A short click followed by silence can mean the logic board is receiving the signal but the motor is not engaging. A rapid whir with a moving chain but a still door points to a disconnected trolley. Try to describe the sound as precisely as you can.

The broken spring, the most common culprit

A garage door weighs far more than most people expect. Torsion springs on a bar above the door, or extension springs along the sides, counterbalance that weight so a modest motor can lift it. When a spring breaks, the door suddenly weighs what it truly weighs, and the opener cannot move it.

A broken spring often announces itself. People describe a loud bang from the garage, like a firecracker or a dropped heavy object, sometimes hours before they notice the door will not move. You may see a gap in the coil of a torsion spring above the door. With an extension spring, you may see one hanging loose or stretched oddly.

Never touch, adjust or try to wind a spring. It stores a great deal of energy and can cause serious injury. The safe observations are to look from a distance, to keep people and cars clear and to leave the door alone. Our page on spring repair and replacement explains why this is work for a trained technician and how the replacement is approached.

If you want to understand the mechanics, our guide on how garage door springs work and why they wear describes torsion and extension springs and the cycles they go through during their life.

• A loud bang in the garage, followed by a door that will not lift.
• A visible gap in a spring above the door.
• A door that feels extremely heavy when lifted by hand.
• The opener straining or humming and then stopping.
• One side of the door sitting lower than the other.

The disengaged trolley or the emergency release

Every opener has a trolley, a carriage that rides along the rail and connects to the door through an arm. A red cord with a handle hangs from the trolley. Pull it and the trolley disconnects from the drive, which lets you lift the door by hand during a power cut or a malfunction.

If the trolley has been disconnected, the opener motor will run and the drive will move along the rail, but the door will not follow. Sometimes someone pulled the cord by accident, perhaps with a ladder, a box or a snagged hand. Sometimes the trolley released on its own because of a worn latch or a sudden jolt.

You can look at this safely. Check whether the red cord hangs normally and whether the trolley arm is attached to the door bracket. If you see the trolley sitting loose on the rail or the arm detached, tell the technician. Reconnecting a trolley is usually a simple matter, but it should only be done when the door is fully closed and balanced, never when a spring has failed.

Our guide on using the emergency release cord safely explains when the release is appropriate and what to avoid, including never pulling it with the door open and unsupported.

A stripped gear inside the opener

Many openers use a small gear, often made of plastic or nylon, to transfer the motor's turning force into the drive. Over years of use, or after the opener has struggled against a heavy door, this gear can wear or strip. The motor runs, the gear teeth no longer catch and the drive does not move.

The sound often tells the story. A stripped gear may produce a whirring or clicking from the motor housing, sometimes with a grinding or ratcheting undertone, and the rail or chain may not move at all. If you can see the chain or belt and it does not travel when the motor runs, that points toward the gear or the drive.

This is an opener repair, and it is distinct from a spring issue. In fact a failing spring can cause a stripped gear, because a motor forced to lift a door without help from the springs can damage itself. Our page on garage door opener repair describes how a technician separates a gear or motor fault from a door balance fault.

Drive type affects how this looks. In a chain drive, a broken or slack chain can leave the motor spinning without moving the trolley. In a belt drive, a snapped or slipped belt does the same thing more quietly. In a screw drive, the threaded rod and the trolley nut can wear. In each case the motor sounds alive and the door goes nowhere, so the drive type is one more detail worth mentioning when you call.

If the gear is the cause, you may have a choice between repairing the opener and replacing it. Our page on opener installation explains how a new unit is chosen and fitted.

Cables, tracks and other mechanical reasons

Sometimes a spring is intact but a cable has slipped or snapped, or the door has come off its track. A lift cable runs from a bracket at the bottom of the door up to a drum on the torsion bar. If the cable breaks or jumps off the drum, one side of the door loses its support, and the door may tilt, bind or refuse to lift.

The clues include a door that sits crooked, a cable hanging loose, rollers out of the track and a door that jammed at an angle. Do not try to push the door back into place. A door in this state can fall or twist without warning.

A bent or jammed track can also cause an opener to hum and stop, though it more often stops after moving a little. If you see bends, dents or gaps in the track, leave them alone and mention them when you call.

These situations are covered in more detail on our pages about broken cable repair and off track door repair. In each case the safe response is to stop using the door and keep people and vehicles clear.

Safe checks you can make from a distance

You can learn a good deal without touching anything dangerous. Start by standing clear of the door and listening as you press the button. Is the hum coming from the motor head on the ceiling? Does the chain or belt move? Does the trolley travel along the rail? Does the door budge even slightly?

Look at the door itself. Is it level across the top edge, or does one side hang lower? Are both cables in place? Can you see a gap in the spring? Is the red cord hanging normally? Does the door look square in its opening?

Check the power and the controls too. Try both the wall button and the remote. If neither works but the opener hums, the issue lies with the drive or the door. If the wall button works only sometimes, the problem may involve the sensors or wiring.

Write down your observations. Details like a bang last night or the door felt heavy yesterday are useful clues, and they often help the technician arrive prepared for the likely cause.

If a vehicle is trapped inside, tell us that when you call. A trapped car changes the plan, since the door may need to be made safe to move before anything else can happen. Resist the urge to force the door open by hand, even for an urgent errand. A hurried attempt is how fingers get hurt and doors get bent.

What not to do

The temptation with a stuck door is to help it along. Do not pull the door up by hand with the opener engaged, do not keep pressing the button over and over, and do not try to force the opener to run harder. Repeated attempts can strip the gear, burn out the motor or make a spring problem worse.

Never try to release or adjust spring tension, and never try to hold a heavy door open while standing under it. If a door that seems to have no spring support slips from your grip, it can come down with enough force to cause serious harm.

Do not disconnect the trolley while the door is open unless you are absolutely certain the door is balanced and supported. A door with a failed spring can fall once released.

Our guide on safety rules every household should know sets out the habits that prevent most garage door injuries, and it is worth sharing with everyone in the home.

Why Houston conditions can bring this on

Springs wear with every cycle, but climate adds to the story. Warm, humid air encourages surface rust on springs, and rust can shorten their life. Heavy rain and storm season add moisture to the garage, and a household that uses the garage as a main entrance runs the door many times a day.

Power events are another factor. Storms in the region can cause outages and surges, and an opener that has been through a surge may behave oddly even if the door is fine. If your humming began after a storm, mention it, because it helps separate electrical causes from mechanical ones.

The heat inside a garage in summer can stress plastic gears and electronics, and a gear that has been working hard against an unbalanced door may finally give out on a hot day.

None of this means the problem was unavoidable. Regular attention to noises, balance and visible wear catches many issues before they become a stuck door.

Deciding between repair and replacement

Once the cause is known, the question becomes what to do about it. A broken spring is a repair, and a replacement spring brings the door back into balance. A disengaged trolley is a small fix. A stripped gear may mean a repair part or a new opener, depending on the age and model.

Age matters. An opener that has served for many years and now has a stripped gear may be near the end of its life, and putting a new gear into it may not be the wisest spending. A newer opener might bring quieter operation, better safety features and a battery backup.

But do not replace the opener without checking the door. If the springs are weak or the door is out of balance, a new opener will inherit the same problem and may fail early. A technician who inspects the whole system can tell you whether the door or the opener should come first.

The decision is yours. You should hear the options explained clearly before any work begins.

Think about how long you plan to stay in the home and how much you use the garage. A household that parks inside every day and carries groceries through the door gets more from a reliable, quiet opener than a household that rarely uses it. There is also a middle path: repair the springs and the immediate fault now, and plan an opener replacement for a time that suits you, once the door is balanced and moving freely.

How to describe the problem and what a visit involves

Contact is by phone. Tell us that the opener hums and the door does not move, then add what you can: whether there was a bang, whether the door feels heavy, whether the cord was pulled, whether the problem followed a storm or a power event.

On site, the system is inspected, not just the opener. The technician looks at the springs, cables, drums, tracks, rollers, the trolley and the opener itself. The options are discussed with you before work begins, so you know what is needed and why.

When the work is complete, the finished repair and normal operation are reviewed with you. You can see the door move smoothly and ask what was replaced. If something looks dangerous before the visit, keep people and vehicles clear and wait for a trained technician. Our guide on how a garage door service visit works describes the full sequence.

Questions and answers