An Ajax alarm installs without special tools and without wiring. For a home, allow half a day. The app guides each step, but a few habits make the difference between a reliable system and one that triggers for nothing. Here is the complete process, from unboxing to declaration, with the most common mistakes.
Before you start
Prepare the equipment: the hub, its detectors, the sirens, a smartphone and an internet connection. An Ajax alarm is easy to fit in your own home. If you are still unsure about the setup, first read which Ajax alarm to choose.
Before drilling or sticking anything, make a quick plan: where are the doors and windows, and which route would an intruder take? Note where each device will go. This plan will save you from moving detectors once they are fixed.
Step 1: install the app and create the account
Download the Ajax app and create an account. No subscription is needed: the app, notifications, history and updates are included. You can read more in our article on Ajax alarms without a subscription.
Step 2: plug in and add the hub
Plug the Hub 2 into the mains, then connect it to your router with an Ethernet cable. Insert the SIM cards if you want a backup link. In the app, add the hub by scanning the QR code on the device. It appears in your account within moments.
Place the hub in a central spot, out of sight, and away from large metal masses. All models are in the Ajax hubs category.
Step 3: create rooms and add detectors
Create one room per zone (hall, living room, garage). For each device, tap “Add device”, scan its QR code, give it a name and assign it to a room. Switch the device on when the app asks.
Step 4: test the signal before fixing
This is the step people skip most often, and the most useful. The Jeweller radio link is encrypted and can reach 2,000 m in open field, but walls and metal reduce that distance. Use the app's signal test at the exact spot where you plan to fix the detector. If the level is low, move it by a few dozen centimetres, or add a ReX 2 range extender (€223.72 incl. VAT).
Step 5: place the devices
- Motion detector: about 2.4 m high, aimed so the intruder crosses its field. Avoid a sunny window, a radiator, an air conditioner, a curtain. For example, the MotionProtect (€79.34 incl. VAT) detects up to 12 m.
- Door contact: on the door leaf, magnet aligned with the frame. The DoorProtect costs €46.04 incl. VAT.
- Outdoor siren: high up (above 2.5 m), street side, clearly visible.
- Indoor siren: outside the protected room.
- Keypad: inside, near the entrance, at about 1.40 m, never on the facade.
Once fixed, check that each device reports correctly in the app. See the list of Ajax detectors if you want to add more.
Step 6: create users and set up groups
Invite family members from the app. The hub accepts up to 50 users. Create groups if you want a night mode (ground floor armed, upstairs free) or if you have an outbuilding, garage or workshop. Scenarios let you automate certain actions.
Step 7: run a full test
Arm the system, go out, then come in through the main door. Check the entry delay, the siren triggering and the notification on every phone. Walk in front of each detector to confirm detection. If your hub has a SIM card, also test by unplugging the Ethernet cable: it should keep transmitting.
Step 8: declare the system on police-on-web
In Belgium, every alarm system must be declared on police-on-web within 10 days of being put into service. The declaration must be confirmed every year. The outdoor siren is limited to 3 minutes. All the details are in our article how to declare an alarm system in Belgium.
Mistakes to avoid
| Mistake | Consequence | Fix |
|---|---|---|
| Fixing without testing the signal | Device drops off | Test in the app before fixing |
| Detector facing a sunny window | False alarms | Change the orientation, avoid sun and radiators |
| Keypad on the facade | Code exposed outside | Fit the keypad indoors |
| Indoor siren inside the protected room | Siren easy to neutralise | Place it outside the room |
| Forgetting the declaration | Legal non-compliance | Declare within 10 days, confirm every year |
| Pet immunity badly set | Unnecessary triggers | Set it according to the animal |
A typical installation day
For a home, here is a realistic rhythm: one hour for the app, the hub and the first pairings, one hour for signal tests and detector placement, one hour for the sirens, keypad and users, then the last stretch for the full test and the online declaration. If a device does not get a good signal, do not force it: move it or add a range extender.
When to call a professional
Self-installation suits your own home. If the alarm is for a third party or a business, installation must be carried out by a company approved by the Belgian FPS Interior. Even for a private home, you may prefer to delegate if the house is large, if the radio signal is difficult or if you are short of time.
Our installation and services offer: fitting by Belgium Security Brussels (approved by the FPS Interior, no. 0666948937) for €302.50 incl. VAT up to 10 items within 15 km of Brussels. Beyond that, the call-out charge is €121 incl. VAT. You can add dispatching from €21.78 per month incl. VAT (visual verification, emergency calls) or after-alarm response at €30.25 per month incl. VAT (plus €90.75 incl. VAT per intervention), provided by European Private Security (approved no. 0549945656).
Frequently asked questions
How long does installation take?
Allow half a day for a home.
Do I need tools?
Few. The system is wireless and the app guides each addition by QR code.
What if the signal is weak?
Move the device or add a ReX 2 range extender. Always test before fixing.
Do I have to declare my alarm?
Yes, on police-on-web, within 10 days, with an annual confirmation.
Can I install an alarm for a business?
For a third party or a business, use a company approved by the FPS Interior.
Can devices be reused on another hub?
Yes, they can be re-paired to a new Hub.
Going further
Browse all Ajax alarms in Belgium and the Ajax alarm kits to start with a complete pack. Questions? Use the contact page or call 0800 37 087.