Mains powered smoke alarms

[Sparky1970]

Hi, I have three mains powered smoke alarms in the house, we have recently had the hallway re-plastered and now need replacement mains smoke alarms as the old ones are badly discoloured. The wiring for the old ones have connector choc blocks that are off the lighting circuit, they have used what appears to be 6 core alarm wire (2 for live, 2 for neutral and 2 for interconnect), it does not look like they have wired them from the ceiling roses, Is this acceptable?

 

[lectriclegs]

no

 

[londonboy]

 

[Taylortwocities]

At least the smoke alarms will detect the fire that their own wiring will cause

 

[wingcoax]

The first leg can be 1.0/1.5 t&e. and the rest can be 1.0/1.5 three core and earth. What you have is totally wrong.

 

[Sparky1970]

I've have two choices then, remove completely and use battery alarms or replace alarm wire. Why would they use alarm wire? They are probably really old alarms so not sure what the standard was then. I only found out when we decided to get our hallway decorated

thanks for your replies

 

[OwainDIYer]

Why would they use alarm wire? They are probably really old alarms so not sure what the standard was then.

Using low voltage wire for mains wasn't acceptable in 1930, never mind 2010.

 

[rebuke]

Can you upload a pic of the cable and the connection on to the lighting circuit?

 

[holmslaw]

..

 

[Sparky1970]

View media item 27065
This is a pic of the ceiling, you can see the 6 core alarm cable coming through hole. The other side of the connector block is a fitting for old mains alarm. Cant show a pic of the connection to the lighting circuit as it is not easily accessible, will have to lift floor boards.

 

[Taylortwocities]

View media item 27065
This is a pic of the ceiling, you can see the 6 core alarm cable coming through hole. The other side of the connector block is a fitting for old mains alarm. Cant show a pic of the connection to the lighting circuit as it is not easily accessible, will have to lift floor boards.

That is horrendous and not suitable for use with mains voltages. It must be disconnected immediately before there is a fire (!) or someone is electrocuted.

You'll need to trace the cables back to their connection to the mains to make sure its all removed. That may involve lifting floorboards etc.

 

[Sparky1970]

yes, i know but its been in for the last 6 years and we only just discovered it on re-doing the hallway. There are some real dodgy people out there. Already in the process of removing.

 

[Sparky1970]

Question - I have a loft conversion as a bedroom, do I need mains linked smoke alarms? At the moment I have replaced with battery powered alarms due to the fact that I cannot use the same cable routes.

If so, I presume this would also come under 'Part P'

 

[holmslaw]

..

 

[Sparky1970]

Surely part p comes into this as it is rewiring a new circuit? as I say, im using battery alarms which is better than no alarm at all, but seeing as I have a 2nd floor I require linked alarms, hence this would need to be installed via a qualified part p electrician