Visonic Alarm Support: PowerMax and PowerMaster Faults, Batteries, and Whether Yours Is Worth Keeping
By the DC Fire & Security engineering team — installing and maintaining fire and security systems since 2010. Updated July 2026.
Quick answer
Visonic made two big wireless families: PowerMax (PowerMax+, Complete, Pro — the mid-2000s generation in thousands of UK homes) and the newer PowerMaster series. Most 'Visonic problems' are age problems: sensor and panel batteries reaching end of life, GSM modules on retired 2G/3G networks, and panels whose original installers have moved on. PowerMaster systems are still well worth maintaining; PowerMax systems are at the point where the honest engineer conversation is battery-round-and-carry-on versus planned replacement — and the answer depends on how many devices are failing at once, not on the badge.
PowerMax or PowerMaster — and why it decides everything
The name on the panel's front tells you which era you're in. PowerMax (+, Complete, Pro, Express) is the older platform — reliable in its day and often still ticking, but its radio protocol, sensor range and communicator options belong to the 2000s. PowerMaster (10, 30, 33, 360R) is the modern PowerG-based platform: longer battery life, two-way radio, and current app/monitoring paths via PowerManage.
Everything on this page filters through that split: a PowerMaster fault is almost always worth fixing; a PowerMax fault is worth fixing *once* — when the faults start arriving monthly, each £-spend is buying months rather than years, and the replacement conversation becomes the economical one.
The faults that dominate Visonic call-outs
| Symptom | Likely cause | The honest fix |
|---|---|---|
| LOW BAT / sensor battery messages, one after another | The original battery set reaching end of life together — they were fitted together, they die together | A battery round replaces every device battery in one visit; on PowerMax expect it to buy years only if the panel itself is healthy |
| COMM FAIL / no signals to monitoring or phone | GSM module on a retired 2G/3G network, or the PSTN line it dialled out on is gone | Comms path replacement (4G/IP) where the panel supports one; on old PowerMax this is often the fault that tips the maths to replacement |
| Panel beeping / TROUBLE with backup-battery message | Panel standby battery done — the ~5-year item | Standard engineer replacement |
| JAM / interference warnings | One-way radio-era detection reacting to a noisy RF environment | Investigate the source; persistent jamming on PowerMax-era radio is another ageing signal |
| Keyfobs/sensors intermittent at range | Radio range shrinking as batteries and components age | Batteries first, re-siting second; PowerMaster's PowerG radio doesn't have this problem |
| Nobody has the installer code | Orphaned system | Takeover: default/regain access, fresh codes, service, documentation — same routine as any brand |
The keep-or-replace maths, without the sales agenda
A fair rule from the vans: spend once on an old system, plan on the second spend. A battery round or a single sensor swap on a PowerMax that's otherwise behaving is money well spent. But when the same panel needs a comms module *and* batteries *and* a couple of sensors, you're most of the way to the cost of a modern owned system — with none of the range, app control or parts availability that come with it.
Replacement, when it comes, is cheaper than people brace for: a modern Grade 2 wireless system for a typical house lands in the low four figures (the full numbers), you own it outright, and the takeover survey that tells you which side of the line your Visonic sits on is free. Either way you keep police-response eligibility as long as the work is done by a certificated installer.
Orphaned Visonic systems
Visonic's UK installer base has consolidated hard over the years, which is why so many PowerMax and PowerMaster owners can't find anyone who'll answer for their system. The takeover routine is the same as Texecom and Pyronix: an engineer regains programming access, sets fresh codes, services what's there, re-establishes monitoring if wanted, and leaves you with paperwork. On PowerMaster it usually ends with 'keep it, here's the service schedule'; on PowerMax it ends with an honest number for each road.
If your alarm is currently doing the thing that brought you here at 3am, the false-alarm guide triages the noise tonight; the engineer visit sorts the cause.
Frequently Asked Questions
Is my Visonic PowerMax obsolete?
Why is my Visonic alarm showing LOW BAT on several sensors at once?
My Visonic stopped sending alerts to my phone — what happened?
Can another company take over a Visonic alarm?
Are Visonic sensors compatible with other alarm brands?
What does a Visonic repair visit cost?
Visonic playing up — or just old?
We repair and take over Visonic systems across Luton, Bedfordshire, Hertfordshire and North London, and we'll give you the honest keep-or-replace answer on the first visit. £100 +VAT call-out with the first hour included; if replacement genuinely is the better spend, you'll get that in writing, not a hard sell.
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