When to Repair or Replace your Intruder Alarm System
Mike fits an indoor intruder sensor
Quick Answer
Repairing your intruder alarm system is usually the best option if the fault is minor, affordable, and the system is under 10 years old. Replacing the alarm is often the better choice if the system is outdated, unreliable, discontinued, or costing more to maintain than it’s worth.
Alarm faults can be stressful, especially when they affect the security of your home or business as well as being a nuisance. We regularly get calls from customers across Edinburgh and the Lothians asking the same question:
Should I repair my intruder alarm or replace it?
This guide explains how to decide, what warning signs to look for, and when upgrading your alarm system offers better long term value and peace of mind.
Examples of older alarms
What we cover in this guide
Key takeaways:
When repairing your alarm system makes sense
When replacing your alarm system is the best option
Repair or replacement cost comparison
Key takeaways
Intruder alarm systems typically last 10–15 years when maintained properly
Repairs are usually best for newer systems with minor faults
Older systems are more likely to breakdown and trigger false alarms
Frequent faults often indicate end of life equipment
Modern alarm systems offer improved reliability and more advanced features which are easily resolved.
When is it better to repair your intruder alarm system?
A repair is often the most sensible option when your alarm system is still relatively new and the issue is limited to a specific component. Many faults can be resolved quickly by one of our engineers without replacing the entire system.
Your alarm system is under ten years old.
Most modern intruder alarm systems are designed to last well over a decade. If your system is under 10 years old and has been installed correctly and maintained efficiently, faults are usually isolated issues rather than full system failure.
In these cases, repairing your alarm is more cost effective than replacing it, the fault is minor and affordable to repair.
Common intruder alarm repairs we carry out include:
Low batteries
Faulty PIR motion detectors
Door or window contact faults
Keypad or fob issues
Signalling or communication faults
These problems can usually be repaired quickly, restoring full protection with minimal disruption.
The system is still supported by the manufacturer
If replacement parts are still available and the system is supported, repairing it is often the best option and avoids unnecessary upgrades.
When is it better to replace your alarm system?
In some cases, replacing your intruder alarm system provides better long term security, reliability, and value.
Your alarm system is over 10–15 years old
Older alarm systems are more likely to suffer from intermittent faults, unreliable detectors, and obsolete components. Many lack modern features such as:
Smartphone app control
Remote diagnostics
Secure wireless technology
A modern alarm system offers improved protection and ease of use.
You’re experiencing frequent faults or false alarms
If your alarm system requires regular call outs or is triggering false alarms, this is often a sign that components are nearing the end of their service life. At this stage, replacement is usually more cost effective. Repairs are becoming expensive.
A simple rule of thumb:
If a repair costs more than 50% of the price of a new alarm system, replacement is the smarter financial decision. This prevents sinking money into outdated equipment with limited lifespan.
Parts are obsolete or unavailable.
Older alarm systems may use parts that are no longer manufactured. This can lead to delays, increased costs, and unreliable fixes.
Your property or security needs have changed.
Extensions, renovations, new access points, or business changes can all mean your existing alarm system no longer provides adequate coverage. A replacement ensures your system matches your current risk level.
Repair V Replacement cost comparison
New MDS intruder alarm control panel
How long should an intruder alarm system last?
Most intruder alarm systems last 10–15 years with professional installation and maintenance.
Can an old alarm system still be repaired?
Yes, but repairs may not be cost effective due to obsolete parts and increased likelihood of further faults.
Will replacing my alarm system improve security?
Yes. Modern systems provide better detection, and improved reliability.
Need advice on repairing or replacing your alarm system?
At MDS Security Systems, we provide honest, practical advice and will only recommend replacement when it genuinely makes sense.
👉 Request a free intruder alarm quote
