Smoke alarms are an absolutely essential safety device in modern homes, and even a legal requirement in some jurisdictions. Of course, my house has always had smoke alarms fitted: A pair (upstairs and downstairs) of mains-powered alarms with a wired connection between: interconnected so both would sound when either one was triggered.
With my smoke detectors reaching their replace-by dates, and now I have Home Assistant in my life, I sensed a great opportunity to upgrade the system!
My requirements were:
Replace the existing two (hall and landing) alarms.
Add further smoke alarms in the office and garage - both rooms with large amounts of always-on electrical equipment. The office door is kept closed at night and the garage is beneath the house (although not accessed directly) so both needed their own alarms.
Add a heat and CO alarm (not smoke) in the kitchen, again, the door is kept closed at night.
Wireless interconnection between alarms, because getting a wired link between the garage and household alarms is too much work.
Some form of connection to Home Assistant for alerts and system monitoring.
Not require an app, WiFi or the Internet to function.
A web search for "interconnectable smoke alarms" narrowed down by "third-party system interconnection" pretty much led me directly to Aico. Their range of SmartLINK interconnected fire alarms appeared to be exactly what I wanted, and Aico also came recommended to me by an electrician, so it really did appear to be a good bet.
Other systems I came across that are worth a mention are FireAngel and Google Nest Protect. I'd encourage you to investigate them if you're in this market. At the time I was looking, neither of these offered a good way to interconnect to Home Assistant so they didn't meet all my requirements but they are systems that are well liked by many. They may suit you.
Battery or Mains Power?
Aico makes both battery (the 600 series) and mains-with-battery-backup (3000 series) powered alarms. I originally thought I'd have a mixture of these but while planning the system I realised I could easily run mains to all the places I needed alarms.
I did, however, verify with Aico Support that the 600 and 3000 series alarms would interconnect using SmartLINK. Good to know.
Alarm Models
The majority of my alarms need to detect smoke. Aico sells smoke-only alarms (the 3016), but there seemed to be little point not buying the combined heat and smoke alarm (the 3024). Heat alarms can detect slowly smouldering fires before they create smoke so offer an additional level of detection for added peace-of-mind.
The kitchen, obviously, wasn't a suitable place for any sort of smoke alarm and instead required a heat-only alarm. Aico don't actually make a heat-only alarm in the 3000 series, but they do a heat and carbon monoxide (CO) alarm (the 3028) instead. Considering there is a gas hob and boiler in the kitchen, having a CO alarm is a wise addition.
The 3000 series alarms will interconnect via a cable as standard. Wireless interconnection using Aico's SmartLINK system requires an additional module fitted into each alarm.
Alarm Controller
An optional addition to the SmartLINK system is the Ei450 Alarm Controller. This little battery-operated device gives a visual indication of alarms, and allows manual interaction to perform tests of the system and to mute and identify a sounding alarm.
Third-Party Alarm Interface
The Ei414 Alarm Interface is the device that really sold me on the Aico system. It connects to the SmartLINK interconnect and has separate relay closures for fire, CO and service notifications. It will work perfectly with an ESP board (more on that later.)
Shopping List
Here's what I ended up buying:
4 x Ei3024 smoke & heat alarms
1 x Ei3028 heat & CO alarm
5 x Ei3000MRF SmartLINK Module
1 x Ei450 Alarm Controller
1 x Ei414 Alarm Interface
SmartLINK
The Aico system allows interconnection by wired or wireless. At its simplest, the wired connection means all alarms will sound when one is triggered.
Going wireless with the SmartLINK system means the system can get rather smarter: Fire detections can be identified and notified separately from CO detections. Service notifications can be delivered. For this to work, all alarms need to interconnect with the SmartLINK modules.
It is possible to use a mixture of wired and wirelessly interconnected alarms in the same system. This has the limitation that the wired alarms will only ever indicate a fire detection: they won't indicate CO detection separately. Instead, a CO detection will 'look like' a fire detection to the other SmartLINK devices including the Ei414 Alarm Interface. Furthermore, the service indication won't be delivered at all. It's enough of a limitation, in my opinion, to justify getting the SmartLINK modules for all alarms.
A SmartLINK system can have up to twelve devices interconnected as standard*. Most devices occupy a single device 'slot' in the system, although the Ei3028 alarm, with its separate CO and heat sensors, occupies two. My five alarms, controller and Ei414 Alarm Interface therefore occupy eight of the available twelve devices - which is absolutely fine, and gives me room for expansion in the future.
* The manual says to contact Aico Support if you need more than twelve devices. My conclusion is that it will likely work, but they can't warrant it without understanding your particular setup.
A 'house code' process during setup makes all the alarms discover each other.
SmartLINK uses the 868.499 MHz radio frequency and the specs suggest it works at least 100m in free space. My house isn't that big! It is, however, over three floors and with some blockwork internal walls. It's probably less than 10 meters between the outermost two alarms so is well within the specs and, from what I can see, SmartLINK has no problem operating over this distance.
Wiring Up
I'm using the SmartLINK wireless interconnection between my alarms, so the only wiring needed was to get mains power to them all. The wired interconnection would simply require a single core of 1.5mm cable, so it's very simple.
I have a dedicated 6A circuit in the consumer unit in the house for my original two smoke alarms (hall and landing), so with the help of some Wago boxes this was extended to the kitchen, office, and it also feeds a socket in the airing cupboard for the Ei414 Alarm Interface.
A dedicated circuit off the garage consumer unit feeds to alarm in there.
The Hardware
Five alarms and the Ei450 Alarm Controller:
The Aico hardware is NICE. It just feels solid, even though it's plastic. The alarm heads come with dust covers. The mounting plate has more screw holes than could ever be needed. The mains connections to the plate have a firmly-fitted cover. The alarms attach onto the plates with a really satisfying click. They've put a lot of effort into these products.
The Ei3000MRF modules fit snugly into the alarm bodies:
The Alarm Interface
The Ei414 Alarm Interface is the most expensive, and most solid, part of the system. It has a large built-in Li-Ion battery for backup. Functionally it's simple: It closes (or opens, depending on how you wire it) relays for the following situations:
Fire detection
CO detection
Service* required
*A 'service' could be something like failed mains to an alarm, a failed backup battery, that sort of thing.
A key switch on the front of the unit controls how the relays are energised. Because the interface is designed to connect to a third-party system e.g. a tele-call system, the key switch can be used to inhibit alarms in certain situations (maybe during a test) where you don't want the third-party system to receive the alarm notification.
Home Assistant Integration
To get the three relay closures on the Ei414 Alarm Interface into Home Assistant, I knocked up a quick little ESP8266 board using ESPHome.
The board I chose is an Adafruit Feather Huzzah, which has a built-in LiPo charger. I figured, as the Ei414 Alarm Interface has a backup battery, I might as well add one to the Home Assistant interface too.
The circuit is as simple as it gets. Three pins are configured as GPIs with a small debounce. Each GPI pin is pulled high ('on') by the ESP's internal resistor, so the relays in the Ei414 Alarm Interface are wired as normally-open in order to pull the GPI pin to ground ('off') when an alarm is triggered. I've also inverted the input in software so the binary sensors in Home Assistant appear as 'off' most of the time.
ESPHome sensor configuration:
binary_sensor:
- platform: gpio
pin:
number: GPIO12
mode:
input: true
pullup: true
name: "Aico FIRE alert"
filters:
- invert:
- delayed_on: 10ms
- platform: gpio
pin:
number: GPIO13
mode:
input: true
pullup: true
name: "Aico CO alert"
filters:
- invert:
- delayed_on: 10ms
- platform: gpio
pin:
number: GPIO14
mode:
input: true
pullup: true
name: "Aico SERVICE alert"
filters:
- invert:
- delayed_on: 10msI soldered up the board with a header and a separate cable harness. The common ground is just looped through each relay using the crimp ferrules to act as terminal blocks. Finally, I popped the board and LiPo battery into a small ABS box.
For ease of installation I fitted the Ei414 Alarm Interface and ESP board enclosure to a wooden baton. I could, perhaps, have squeezed the ESP Board and LiPo battery into the Ei414 Alarm Interface's box, but it would have been a squash and I don't like putting the ESP WiFi antenna too close to other devices.
On installation, the Ei414 Alarm Interface needs to have its internal backup battery engaged - that's the switch below the red battery sticker in the above photo.
In Home Assistant I did a little bit of further configuration to use proper icons for the sensors. When triggered, they light up red.
System Installation
Installation was really easy. Simply attach the mains to the alarm base, affix to the ceiling, and slot the alarm onto the base with a click. The alarm powers on straight away.
I fitted the Ei414 Alarm Interface into the airing cupboard, chosen because it's relatively central in my house. Yes, I do leave the key in the key switch! Otherwise, I'd lose it.
System Commissioning
The devices need to be 'house coded', where they recognise each other in the SmartLINK system. The Aico manuals are really well written and explain how this works clearly, but simply: You put each device into 'house code' mode where it searches for other devices, flashing its LED once for every device detected. This process can take a while, says the manual, but in practice every device in my system detected all other devices (flashing its LED eight times for eight devices) within a few seconds of all devices being in 'house code' mode.
System Testing
The alarm system needs testing upon installation, and then routinely thereafter.
Testing with the Ei450 Controller
The TEST mode of the Ei450 Alarm Controller will cause all alarms to sound together. Though it works, it doesn't feel hugely useful because all alarms sound at once and no indication is outputted by the Ei414 Alarm Interface. It does, though, serve to test the Ei450 Alarm Controller itself.
Testing with the Test Buttons
This is my preferred way to conduct a test. Each alarm has a test button which, obviously, causes it to sound (loudly; wear ear protection!). Connected alarms start sounding after a few seconds. Upon releasing the test button, the alarm stops sounding immediately, and connected alarms continue to sound for some seconds. This means you can confirm the connected alarms did, in fact, sound; you really can't hear distant alarms sounding when the alarm at the end of your arm is blaring; did I mention it's loud?
A cool additional feature of the test process: The combined heat & CO alarm alternately 'detects' fire and CO on subsequent test button presses. First test press: fire alarm. Second test press: CO alarm. The sound is the same but the alarm itself has indications showing what alarm is detected so you can take the appropriate action (e.g. open windows for CO, close windows for a fire.)
Test alarms like this will only be reported to the third-party system by the Ei414 Alarm Interface if the key switch is in TEST mode. It stops the third-party system getting false alerts, which perhaps isn't a problem for my Home Assistant integration, but might be if the system automatically called the fire service!
The test procedure is therefore:
Turn Ei414 Alarm Interface key switch to TEST
Activate test on Ei450 Alarm Controller by pressing the button until TEST LED lights blue
All alarms should ring
Button test each alarm, one-at-a-time
The alarm sounds
After a few seconds all other alarms should ring and the FIRE or CO signal should be reported to HA (applicable signal from the alarm under test)
Release the button, the alarm stops sounding
Other alarms sound for a further 3-4 seconds
Turn Ei414 Alarm Interface key switch to ON
Concluding Thoughts
This all went very well and I'm delighted with the result.
The Aico hardware is lovely (yes I'm geeking out over smoke alarms - proving there's no end to my geekery) and everything in the setup and commissioning processes worked exactly as the manuals suggested it would. My pre-sales experience with Aico Support was also great: they replied quickly and resolved my question straight away.
The Ei450 Alarm Controller is probably not necessary; tests can be performed using the test buttons on the alarms themselves, and even in a large house with lots of alarms like mine, if the alarms are sounding, I think it would be fairly straightforward to identify which one was triggered. That said, it's the cheapest part of the system so I don't regret buying it.
I will expand the system further by adding smoke & heat alarms into the bedrooms; at the moment we don't have this and it's recommended by some places for households who sleep with the doors closed. Again, why wouldn't we want as much protection as we possibly can get? Adding four further alarms will max my SmartLINK system out at 12 devices, still within its specs.
The Aico hardware isn't especially cheap, but heck, you can't put a price on safety. It's much cheaper than a professional/commercial system would be.
All in all, the Aico system fitted my project brief exactly. I'm pleased to have discovered Aico as a vendor, the SmartLINK system appears to work well and fundamentally I now sleep more soundly knowing my house is much more thoroughly covered with smoke and heat detection than it was before.
Commenti