Where is your smoke alarm situated? If it’s in the hallway, an integral CO detector is superfluous so you may add well save your money.
Yes it’s in the hall way and we already have a CO detector near our wood burner.
As well - poxy auto-correct on my phone. :twisted:
If your mains-powered detector is in a hallway, you should replace this with an optical type with battery back-up. I only fit AICO smoke alarms - this one in particular.
It is reasonably priced (£23 for ten years is a drop in the ocean) and easy to install. If no interlink, it’s a simple live & neutral connection to the inbuilt connector block.
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If you recommend it, I’d trust you.
However, although you say ‘ten years’, I can see no mention of a guaranteed 10 year life on the web site. Is it definitely going to last for 10 years (but not the battery of course)?
If you recommend it, I’d trust you.
However, although you say ‘ten years’, I can see no mention of a guaranteed 10 year life on the web site. Is it definitely going to last for 10 years (but not the battery of course)?
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The ten years is the life expectancy - it will have a replace by date on it when you get it. The alarm will chirrup every forty seconds or so when the battery needs changing. All smoke alarms should be replaced after ten years as a matter of course as although it will work while pressing the test button, it’s not guaranteed to work in a fire situation because of the build-up of dust over time.
The ten years is the life expectancy - it will have a replace by date on it when you get it. The alarm will chirrup every forty seconds or so when the battery needs changing. All smoke alarms should be replaced after ten years as a matter of course as although it will work while pressing the test button, it’s not guaranteed to work in a fire situation because of the build-up of dust over time.
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OK. Fair enough.
Actually, the old mains-powered smoke alarm, which is still in place and has been as long as we have been here - 15 years! - seems still to be working, at least in some respects.
The light flashes every minute or so, which I assume indicates it is still working.
I haven’t replaced the back-up battery, so in a power cut I’m sure it won’t be working.
As you say, it may look as if it’s working, but may not work in a real fire situation.
Having said that, when we had a new gas fire put in in the adjacent room a couple of months ago, they did the usual smoke test and the alarm went off! I think that’s pretty good for over 15 years old!
I have now had a good look at this smoke alarm.
I opened it and found that it has no trace of any mains voltage in it. Neither does it have a back-up battery.
All I can assume is that it is somehow tied in to the house alarm system. I must look closely through the documents.
I’m glad that I didn’t go out and buy a replacement mains-powered smoke alarm as that wouldn’t replace this directly.
Photos attached.
A good job you checked. 
That smoke alarm will be fed from your burglar alarm power supply and linked into a pair of terminals programmed to act as a fire zone. In theory, if it does activate, your burglar alarm will also ring but with a different type of alarm sounder - usually pulsed depending on make of alarm panel.
We have our alarm checked every year, but the engineer has never mentioned the smoke alarm.
Am I right in assuming that, like all smoke alarms, the sensor would deteriorate over time?
If so, I could ask them how much they’d charge to replace it.
Having made further enquiries, the old smoke alarm model we presently have, and its more recent direct equivalent, have now both been discontinued.
The replacement offered now by the manufacturers, Aico, requires a 9V battery for back-up. As our intruder alarm already has a back-up battery in case of mains failure, I see no need for this.
The other thing is that if I am obliged to replace the 9V battery every year or so, why bother with an intruder alarm-powered smoke alarm anyway.
Consequently, I’ve sent for a lithium battery-powered smoke alarm with a 10 year guarantee. If the battery fails before then, I’ll claim a replacement!
I’ll remove the old one and, as the existing cables are no danger, being 12V, I’ll leave them disconnected above the new smoke alarm.
I have to sort out my own mains powered alarms soon. They too seem to be discontinued which is annoying or I could have left the base plate in place and just slotted on the new alarm unit. I’ll probably go for battery alarms making sure that they are big enough to cover where the old one was. As for the wiring to them I’ll just put it in a terminal block and shove it up into the ceiling.
I suggested the same on a certain DIY site a couple of weeks ago and was told in no uncertain times that I mustn’t do that! The terminal block must go in a container first, and to do that would mean making a bigger hole in the ceiling.
In my case, fortunately, the smoke alarm isn’t actually mains-powered, but powered from the intruder alarm at 12V, so I’m going to ignore the ‘warning’!
Did they give any reason why?
Yes, that to leave any mains wiring, even in an unprotected choc block, in the loft would be dangerous and illegal. I believe them, as I have heard similar safety concerns elsewhere on the forum.
Incidentally, the guys giving advice on that forum are mostly qualified electricians.
Not an issue for me although it almost certainly would contravene wiring regulations. The loft has monster thick insulation and is fully boarded above that. The other two detectors are downstairs.
I may use wired detectors anyway if the new models are big enough to cover the place the old ones were - I don’t want to be repainting ceilings. I suppose another option would be to just add additional detectors and leave the old ones in place although that would look a little odd.
Yes, ours has thick insulation and is boarded over in that location.
I’m not one to bother with regulations normally, but if there is the likelihood of any possible consequences that might invalidate my house insurance, I do take note!
It does contravene on several counts
…as does cables through monster thick insulation
How about 12V cables?
There is no requirement to protect ELV (your “12v” cable) cables from loft insulation but the should be minimum 50mm distance from any LV (“mains”) cable
…and of course that 12v cable will still “go” somewhere and, as an assumption, will connect to a transformer so that still does bind it to the regulations that are implied from that - in other words your 12v cable is still “connected” to the mains via a transformer
Thanks.
I now have the replacement smoke alarm and notice that there is a nice convenient hollow all around the base. That would be ideal for housing the old cables, when I’ve cut off the bare ends, so they won’t be near anything else and will not touch anything conductive, so I won’t have to stuff them back into the loft.