Mains interlinked smoke detectors

Mdljk · Dec 11, 2021

Hi. My property is 25 years old. It has the original Fire Angel mains interlinked smoke detectors. One on the ground floor passage and one directly above on the first floor hallway ceiling. They have become unreliable - one going off no longer sets the other off. I have replaced Duracell 9v batteries. The light show green but the ‘test’ button can sometimes result in a muffled alarm with no interconnection. After 25 years they may be ready for retirement.

Can I replace ‘like for like’ - They have the three pin interconnector or…… are they obsolete requiring total replacement?

Thanks

littlespark · Dec 11, 2021

Smoke detectors should be changed after 10 years, so I’m not surprised it’s faulty.

If one is not setting the other off, there may be a loose connection on the interlink cable.

Personally, I would replace with aico. Much more reliable.

brianmoooore · Dec 11, 2021

If they're original to the house, they should have been replaced by now, the replacements themselves replaced and those replacements should now be middle aged.
There could be a problem with the link cable between them, but it's more likely they are simply faulty.
As littlespark has said above, best to replace them with Aico alarms, which should be able to be connected to the existing cables. Aico make photo-electric and ionisation (google the difference) mains operated versions, with PP3 back up batteries, and also mains versions with sealed for life batteries that should last the full 10 years.

Mdljk · Dec 12, 2021

brianmoooore said:
If they're original to the house, they should have been replaced by now, the replacements themselves replaced and those replacements should now be middle aged.
There could be a problem with the link cable between them, but it's more likely they are simply faulty.
As littlespark has said above, best to replace them with Aico alarms, which should be able to be connected to the existing cables. Aico make photo-electric and ionisation (google the difference) mains operated versions, with PP3 back up batteries, and also mains versions with sealed for life batteries that should last the full 10 years.

Thanks - I am about to order

“Set of 2 x Aico EI141RC Ionisation Smoke Alarms Mains / 9V Battery Back Up”.

Before I do…… will the wiring be a straight swap-out into this 3 terminal block?

[ElectriciansForums.net] Mains interlinked smoke detectors

brianmoooore · Dec 12, 2021

No, everything has to be changed except for the wiring.
The Aico terminal box is less than generous with space for two cables, but it can be done.

Mdljk · Dec 12, 2021

brianmoooore said:
No, everything has to be changed except for the wiring.
The Aico terminal box is less than generous with space for two cables, but it can be done.

Thanks

So, there is a standard single plastic backbox above that accepts the existing terminal snd allows the loose wiring to tuck up into. I guess the Aico comes with its own mounting backplate. Is it not just a case of removing the existing ‘loom’ from the terminal block - mounting the Aico backplate onto the existing backbox- using the provided Aico loom to connect the device into the existing terminal block which provides live, neutral and the interconnecting signal wire?

brianmoooore · Dec 12, 2021

If there's a backbox already fitted in the ceiling, as you say, then I would cut the plug off of the existing connector to the alarm, as close to it as possible, and use those wires to connect to the terminal block in the Aico base.
There are plenty of mounting holes in an Aico base, some of which will match up with the spacing of the back box screws.
Too late if you've already ordered them, but I would use a photo electric sensor downstairs an an ionisation one upstairs.

Mdljk · Dec 12, 2021

brianmoooore said:
If there's a backbox already fitted in the ceiling, as you say, then I would cut the plug off of the existing connector to the alarm, as close to it as possible, and use those wires to connect to the terminal block in the Aico base.
There are plenty of mounting holes in an Aico base, some of which will match up with the spacing of the back box screws.
Too late if you've already ordered them, but I would use a photo electric sensor downstairs an an ionisation one upstairs.

Cheers Brianmoooore - Got you - no provided connecter - drop connection down for L. N. IC directly into terminal box

I was waiting your reply before placing order - Amazon have a pair of Aico ionisation at less than £34 delivered so I didn’t look further. Will take your advice and source separate ionisation and photo electric to interconnect

Mdljk · Dec 12, 2021

Mdljk said:
View attachment 92892
Cheers Brianmoooore - Got you - no provided connecter - drop connection down for L. N. IC directly into terminal box

I was waiting your reply before placing order - Amazon have a pair of Aico ionisation at less than £34 delivered so I didn’t look further. Will take your advice and source separate ionisation and photo electric to interconnect

Done that now, only £5 more. Many thanks Brianmoooore