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Burglar alarm repair in London

An alarm that keeps going off, beeps every few seconds, shows a tamper or battery fault or will not set. Book the call-out online any time, day or night. Engineers attend Monday to Saturday, 08:00 to 19:30, with the first hour of diagnosis included, and tell you the fix before doing it. Wired, wireless and hybrid alarms in homes and businesses, across London and the M25.

• Book the call-out
• Call 07414 155520

London number 020 8175 5557

8am to 6pm, Mon to Fri

Standard call-out

£99 inc. VAT

First hour of diagnosis included.

8am to 7:30pm, Mon to Sat

Priority call-out

£150 inc. VAT

Priority dispatch, first hour of diagnosis included.

Need a new alarm instead? Alarm packages start at £699 inc. VAT.

Book a burglar alarm repair call-out

Choose standard or priority, tell us what the alarm is doing and where, then pay the call-out fee to confirm. You get a confirmation and an ETA on the way.

What we repair

Houses, flats, shops and offices, across London and inside the M25, whether we installed the alarm or another company did.

• Control panels and keypads, repaired or replaced on the existing wiring
• Standby batteries in the panel and the outside sounder
• Movement detectors and door or window contacts
• Outside sounders (bell boxes)
• Tamper circuits and wiring faults
• Wireless sensors that have dropped off the system
• App and communicator faults on alarms that alert your phone
• User codes, fobs and settings

Common faults, and what they usually are

Keypad beeping with a battery or power warning

Most often the standby battery in the control panel has aged and no longer holds its charge. The same warning can come from a wireless sensor battery or from the mains supply to the panel being off, so the engineer tests before replacing anything.

Going off for no reason when it is set

Usually a movement detector reacting to a pet, an insect, a draught, a heater or direct sunlight, or a contact on a loose door or window. The event log usually shows which zone was responsible.

Tamper fault

The protective circuit that runs through the covers and cables has been broken. Usual causes are a loose cover on a detector, keypad or outside box, or a cable disturbed during decorating or building work.

The alarm will not set

Most panels will not set while a zone is open or a fault is outstanding: a door or window not fully closed, a contact that has moved out of line, a broken wire or a failed detector.

The box outside is sounding on its own

Wired outside sounders have their own backup battery and sound by themselves if they lose the supply from the panel, so it often points to a failing battery, a cable fault or a worn tamper switch in the box.

Beeping or sounding after a power cut

During a power cut the system runs on its standby battery and many panels beep to report the loss of mains, which is normal. A battery warning that is still there days after the power is back usually means the battery needs replacing.

Keypad blank or not taking the code

A blank keypad has usually lost power: a blown fuse, a wiring fault or a system with no mains and a flat battery. A refused code can be a lockout after several wrong attempts.

App offline or a communication fault

The link between the panel and the app has dropped, usually because the router, the Wi-Fi password or the broadband has changed, or because the communicator or its SIM has failed.

These are the usual causes, not a diagnosis. The engineer tests for the actual fault on site before any repair.

How the call-out works

1. 1

   Book online, any time

   Pick standard or priority, tell us what the alarm is doing and where, and pay the call-out fee to confirm. Day or night, the booking goes straight through.

2. 2

   We confirm the visit

   You get a confirmation and an ETA. Engineers attend Monday to Saturday, 08:00 to 19:30.

3. 3

   The first hour: finding the fault

   The engineer reads the event log and tests the panel, the batteries, the detectors and the sounder to find the fault, and tells you what the fix is before doing it. A false alarm that comes and goes can take a second visit to pin down.

4. 4

   Repaired, or priced to replace

   If it needs parts, more time or a new system, you get a written price for either route before any further work. The job is photographed and signed off by you.

Book the call-out

What our customers say

Google reviews: Excellent, 4.7 out of 5 from 3 reviews (read them on Google).

Trustpilot: Average, TrustScore 3.7 out of 5 from 1 review (read them on Trustpilot).

• Ian, November 2026: 5 out of 5 stars, on Trustpilot (CCTV installation)

  Excellent service from AI Protech Ltd! They installed a CCTV security system at my home, and I couldn't be happier with the results. The team was highly professional, reliable and knowledgeable throughout the entire process. The installation was completed to a very high standard, and the pricing was extremely competitive. Great quality, excellent customer service and outstanding value for money. I would highly...

• Iann Cohen, November 2026: 4 out of 5 stars, on Google

  Profissional , Reliable company Recommend

• Knighthak Enquiries, November 2026: 5 out of 5 stars, on Google (Intercom repair)

  Fast , quick and reliable ,intercom system fixed the same day ,easy web-form agreed in one call ..Recommended

• Jamie Bishop, November 2025: 5 out of 5 stars, on Google (Smart heating)

  Adham was excellent and went the extra mile to get our smart heating system up and running. I'd recommend the company and him to everyone I know. He really knows his stuff and completed the work to a really high standard.

While you wait for the engineer

Six things that help, none of which need a cover taking off.

• If you think someone has broken in, call 999. If smoke detectors are linked to the alarm, check for smoke.
• Enter your user code at the keypad: that silences most alarms, even when the fault stays on the display.
• Note which zone or device the keypad names.
• Close internal doors and windows, and keep pets out of rooms with movement detectors.
• Do not open the control panel, the keypad or the outside box, and do not disconnect the mains or the battery: the panel has mains wiring inside, and cutting the power can set off the tamper.
• Have the make and model of the control panel ready when you book.

Alarm repair questions

Anything else, contact us or ask Katie, our assistant.

Other repairs: CCTV repair and intercom and door entry repair.

How much does a burglar alarm repair call-out cost in London?

Ai Protech's repair call-out is a fixed fee: £99 inc. VAT for a standard visit (Monday to Friday, 08:00 to 18:00) or £150 inc. VAT for a priority visit (Monday to Saturday, 08:00 to 19:30). Both include the first hour of diagnosis. If the fix needs parts, more time beyond the first hour or a replacement, the engineer gives you a written price before doing any further work.

Can I book the call-out at night or on a Sunday?

You can book and pay for the call-out online at any time, day or night. Engineers attend Monday to Saturday, 08:00 to 19:30 (no night or Sunday visits), and we confirm the earliest visit within those hours.

Why does my alarm keep beeping?

A repeating beep at the keypad is usually a fault warning, not an intruder alarm. Most often the standby battery in the control panel has reached the end of its life: they usually last around three to five years, less in a warm place. It can also be a low battery in a wireless sensor, a fault on the mains supply to the panel or a tamper, and the keypad normally says which. Entering your user code usually silences the beep, but it comes back until the cause is fixed.

Why does my alarm keep going off for no reason?

When it is set, the usual causes are a movement detector reacting to a pet, an insect on or inside the detector, a draught, a heater or direct sunlight, or a contact on a loose-fitting door or window. When it is not set, movement detectors are ignored, so it is more likely a tamper, a panic button, a smoke detector linked to the alarm, a power fault or the outside sounder reacting to a loss of supply. The engineer reads the event log to see which zone or device was responsible. A fault that comes and goes can need a second visit.

How do I stop the alarm sounding while I wait?

First make sure it is a fault and not a real alarm: if you think someone has broken in, call 999, and if smoke detectors are linked to the alarm, check for smoke. Then enter your user code at the keypad: that silences most alarms, even when the fault stays on the display until it is fixed. Do not open the control panel or the outside box and do not disconnect the mains or the battery. The panel has mains wiring inside, and cutting the power can set off the tamper instead of silencing the alarm.

I have no codes for the alarm, or I have forgotten mine. What can be done?

An alarm under a monitoring contract or with police response stays with the company that holds the contract, so contact that company. For any other alarm, book the call-out and tell us the make and model of the control panel. On the visit the engineer checks whether the panel will accept a reset so that new codes can be set. Some panels are locked by the company that fitted them: then the choice is to ask that company for a handover, or to have a new control panel and keypad fitted on the existing wiring and detectors, where they are sound and work with the new panel, priced in writing first. If the alarm came with a rental or subscription contract, check that contract first, because the equipment may still belong to the alarm company. We may ask for proof that you own or occupy the property before any code is changed.

Can you repair an alarm with a monitoring contract or police response?

Not while it is under that contract. An alarm with a monitoring contract or police response is normally maintained by the company that holds the contract, so contact that company. Work by anyone else can cause false signals and can affect the contract or the police response. For audible-only alarms and alarms that alert your own phone, book the call-out here. If your insurer sets conditions for the alarm, check your policy wording.

Is my old alarm worth repairing, or should I replace it?

Repair, when the fault is a battery, a single detector, a door contact, the outside sounder or a damaged cable on a panel that is otherwise sound. Replace the control panel and keypad when the main board or the keypad has failed on a model that is no longer made, or when the panel is locked and cannot be reset: the existing wiring and detectors can often stay, and the swap is priced in writing after the diagnostic. When faults keep coming back after a repair, a new alarm can be the better route. The engineer tells you which after the one-hour diagnostic, with a written price before any further work. If the whole alarm is being replaced, a new wireless alarm for a flat is £699 inc. VAT, and the Family Home package is £1,099 inc. VAT.

Will it be fixed on the first visit?

Not always. A battery, a loose cover or a contact out of line is normally found within the first hour. A cable break inside a wall or a false alarm that comes and goes may not be, and can need a return visit. An outside box that cannot be reached safely from a ladder needs access equipment, which is priced in writing first. Anything beyond the first hour is priced in writing before the work.

Can you repair an alarm that another company installed?

Yes, unless it is under a monitoring contract: in that case it is normally maintained by the company that holds the contract, so contact that company. Tell us the make and model of the control panel when you book. Faults in the batteries, the detectors, the door contacts, the outside sounder and the wiring can usually be traced and repaired, where parts for that make are still made. Changes to the programming need the engineer code: if the company that fitted the alarm kept that code, the engineer checks whether the panel will accept a reset, and we may ask for proof that you own or occupy the property first. If the panel is locked, the choice is a handover from that company or a new control panel and keypad fitted on the existing wiring and detectors where they are sound, priced in writing first. If the alarm came with a rental or subscription contract, check that contract first, because the equipment may still belong to the alarm company.

Which alarms do you work on?

Wired, wireless and hybrid alarms that are audible-only or alert your own phone, whether we installed them or another company did, including Ajax, the wireless system we install. Tell us the make and model of the control panel when you book, so the engineer knows what is fitted. We take on a repair where parts for that make are still made.

Do you offer a yearly alarm service?

Yes, for alarms we installed and for alarms fitted by other companies that are not under a monitoring contract. CarePlan Home at £199 a year inc. VAT gives an annual health-check visit for your cameras and alarm, with remote support included. CarePlan Home Plus at £349 a year inc. VAT gives two service visits with firmware and app updates. If your insurer sets conditions for the alarm, check your policy wording. To take one out, ask under Care plans on the CCTV & Security page, aiprotech.co.uk/services/cctv-security#care-plans, or call 020 8175 5557. See the care plans.