Operation and controls
Why does my garage door reverse before closing?
A UK garage door that reverses before fully closing is almost always its safety reversal system working correctly under BS EN 12453 — it has detected what it interprets as an obstruction. In most cases this is a dirty or misaligned photocell rather than a real obstruction, and realigning or cleaning it typically costs £80–£180.
What is happening technically
UK power-operated garage doors are required to stop and reverse if they meet resistance while closing, as a safety measure to avoid crushing a person, pet or object. This is achieved through a combination of the photocell beam across the opening and force limitation built into the operator, which senses increased resistance on the motor.
The usual culprits in order of likelihood
Start with the photocells — check both lenses are clean and nothing is blocking the beam, including spider webs, which are a surprisingly common cause. Next check the track for any obstruction or debris the door is catching on near the bottom. If both are clear, the operator's force setting may have drifted and need readjusting by an engineer.
| Cause | DIY fixable | Typical cost |
|---|---|---|
| Dirty or misaligned photocell | Often | £0–£180 |
| Obstruction or debris in track | Often | £0 |
| Drifted force/limit setting | No | £0–£120 |
| Worn or slack cable catching | No | £120–£250 |
Prices include VAT. A £40–£80 call-out fee may apply where an engineer visit is needed.
Questions people ask
- Is it safe to keep using a door that reverses randomly?
- Yes, in the sense that reversing is the safety system doing its job rather than failing dangerously. But a door that reverses unpredictably is inconvenient and worth diagnosing, since it can also mask a genuine developing fault such as a stiffening spring.
- Can I turn the reversal sensitivity down myself?
- This is not recommended. Force limitation settings on a power-operated door are a safety feature governed by BS EN 12453, and setting the force too high to stop reversal can turn the door into a crushing hazard. Leave force adjustments to a qualified engineer.
- Does cold weather affect reversal behaviour?
- Yes, indirectly — cold weather can stiffen grease in tracks and hinges, increasing resistance on the door, which can be enough to trigger the force-sensing reversal on a UK operator during winter months even when nothing is actually blocking it.
UK standards and regulations referenced
- BS EN 12453:2017+A1:2021
- BS EN 12445
Related
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