Safety edge and photocell repairs

• Replacement safety edges for the bottom rail of electric roller doors
• Photocell pairs replaced, aligned and tested across the opening
• Wiring and control box faults traced when the device itself isn't to blame
• Door tested after the repair to check it stops and reverses as it should

What are the signs of a faulty safety edge or photocell?

The usual signs are a door that won't close, or one that stops or reverses as it closes when nothing is in the way.

Other clues include a split or flattened safety edge, a photocell indicator light that stays off or flickers if your photocells have one, or a door that started misbehaving after the bottom rail was knocked or a photocell was bumped. On some systems the door will only close while you hold the button down, and some control boxes show a warning light when a safety device reports a fault.

These symptoms aren't always caused by the device itself. A loose connection, a damaged cable where it runs up the guide rail, or a control box fault can look the same. That's why the engineer tests the whole circuit, not just the part that looks damaged. Our roller garage door safety guide explains how these devices protect people, pets and cars.

What can you check before requesting a visit?

You can safely clean the photocell lenses, check nothing is breaking the beam, check the photocells haven't been knocked out of line, and look at the safety edge for visible damage.

1. Look for anything in the opening: bins, bikes, plants or cobwebs across the photocells.
2. Wipe the photocell lenses with a soft, dry cloth.
3. Check both photocells face each other squarely. If one has clearly been knocked, gently line it back up, following the manufacturer's instructions.
4. Look along the safety edge for splits, flattened sections or a loose cable.

Never tape over, bridge or disable a safety device to make the door close. If the door still won't behave, switch it off at the isolator if it's moving unpredictably, keep people and cars clear, and request a visit.

How much does it cost to replace a safety edge or photocells?

A replacement photocell pair costs £99–£189 inc VAT and a replacement safety edge costs £159–£295 inc VAT, both fitted, with the price agreed before we come out.

Each price covers the new device, fitting it, connecting it to the control box and testing the door afterwards. If you tell us what the door is doing and send photos of the bottom rail, the photocells and the control box label, it helps us work out which device is likely to be at fault before the visit.

If the cause turns out to be wiring or the control box, the engineer explains what's needed and quotes before doing any further work. Other fitted prices are on our prices page, and all home prices include VAT at 20%.

Why do safety devices matter on an electric roller door?

Safety devices matter because an electric roller door is a heavy powered machine, and the safety edge and photocells are what stop it closing onto a person, a pet or a car.

When a powered door is put into service, it is force-tested to BS EN 12453 with its safety devices working, as part of meeting the Supply of Machinery (Safety) Regulations 2008 (as amended). A damaged or bypassed device means the door may no longer behave as it did when it was commissioned.

Test the safety edge and photocells monthly, as the manufacturer's instructions describe. If the door doesn't stop or reverse during a test, stop using it until it has been checked. Adding photocells to a door that only has a safety edge is a worthwhile upgrade too; our battery backup and safety upgrades page covers it.

How does a safety device repair visit work?

A safety device visit runs in four steps: you describe the fault, we confirm the visit price, the visit is booked, and any further parts are quoted before they're fitted.

1. Tell us what the door is doing and what you've already checked, with photos of the bottom rail, photocells and control box label if you can.
2. We confirm the price of the visit and the likely replacement part.
3. The visit is booked, with the date confirmed in writing once an engineer is available.
4. The engineer tests the circuit, replaces the faulty device, and tests the door before handing it back.

Before leaving, the engineer shows you how to carry out the monthly test on your door, so you know what normal behaviour looks like and can spot a problem early.

Guide prices for safety edge and photocell repairs

Guide prices for homes. The visit price is agreed before we come out, and any parts are quoted before they are fitted.

Guide prices for homes, last reviewed 25 October 2026. Your written quote is the price. See the full price list.

How does a visit work?

1. STEP 01

   Tell us about the door

   Describe the door and what you need, with a photo or video if you can.

2. STEP 02

   Agree the visit price

   We confirm the visit price before anyone comes out.

3. STEP 03

   Visit

   The engineer finds the cause and makes the door safe where possible.

4. STEP 04

   Parts quoted first

   Any parts are quoted before they are fitted, so you decide.

Questions about safety edge and photocell repairs

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