Smoke alarm problems

[euphoricmess]

Hi

I recently had my house rebuilt, involved full rewiring etc. Now we are about to move in we need the final build certificate. Its been a while since the electrics were in etc, 10 months or so and they left saying all working fine, but left the electrics off.

Anyway, all is working, bar the mains smoke detectors. They work battery powered, and if you press the button and hold it they alarm to test working, but when you switch them on at the mains the two of them just constantly alarm.

We cannot get the building certificate without this and the electrician is saying it is likely to be something else and have we had other people in as it worked when he was last year.

There are two alarms in the house, and they both alarm when the mains is switched on, a type of loud cricket noise rather than that of it normally alarm. Both also Alarm when pressed.

Now with mains off but batteries in they may sometimes chirp once or twice.

Add to that he is not fit to work at the minute.

Any idea what the problem is? I have attached photos.

Many thanks

 

[malcolmsanford]

Have you tried changing the batteries, with the power off for 10 months as you say, those alarms would have been working on battery back-up.

I don't recognise the ones you p[osted but it is worth a try.

 

[telectrix]

i use these. as ^^ malcolm says, probably batteries. you need a small screwdriver to release the head and it slides off to one side. be careful when disconnecting batteries. i had 1 last week where it was so tight, it ripped the terminal out of the battery. you should have a leaflet showing how to remove the head.

 

[euphoricmess]

Replaced batteries and they are still ok when mains switch not on, but alarm when mains switch arm. Alarm loud and continuous

 

[telectrix]

could be one or both contaminated by dust. try removing each head in turn and see if fault can be traced to one or the other.

 

[malcolmsanford]

Tel seems to know these ones, but if the batteries are good, and there is main voltage to them then it looks like faulty head.

Is there definately 230 volts going to them? could try and see if there is dust in them, again not knowing these type directly, but others that I have worked on, do tend to play up and and give a false alarm if they are dusty or dirty.

Remove the head and blow them out. you could use lung power to just clear them.

 

[euphoricmess]

Thanks both, there is progress.

When the one downstairs is off the mount, then i turn the mains on, the one upstairs alarms (still connecting to mains), then when I switch them arround, with the one downstairs installed correctly and the one upstairs off, no noise at all....

So I am assuming, (and im not stupid, but electrics is not my thing) that it is something to do with the one upstairs?

Any tests I can do before having to go out and buy another?

 

[telectrix]

i reckon it's dust esp. if he's been rebuilt, dust covers left off. hairy assed builders making loads of dust. these units are £20 each inc. vat. buy 2 and swap the heads. no need to disturb wiring.

 

[euphoricmess]

Dust covers were on, but may have been taken off or fallen off before carpet put down. Cant be certain as dont know where they went (the covers).... They are an Ei141...

 

[euphoricmess]

Update, they make the odd beaping noise now they are attached but no electricity to them.

When the alarm is going, both are sounding and both are flashing red light and have green light on constant

 

[euphoricmess]

Further investigation into it shows that if you replace either of the heads on the downstairs mains bracket they work fine when the mains is on. Either on the one upstairs and the alarm goes off.

Could the wiring be wrong on the second one?

Thanks

 

[malcolmsanford]

It could very well be. I assume there is 3 wires coming from downstairs one to the upstairs one.

Here is the file for the alarm, you can see if it is connected correctly. Make sure though that you have all the power switched off to the circuit before you stat poking about.

http://dl.owneriq.net/5/5b7a26a2-93cd-43c8-9370-644a4bdd79dd.pdf

 

[PC Electrics]

I was going to suggest that you check the polarity at both. Either check it yourself or get someone in to do it for you.
I use Aico alarms too and have never had any issues with them. I'm unfamiliar with the specific fault description you give, so why don't you ring Aico technical? You should have instructions which will have the number or check out their web site: Aico | Smoke, Heat & CO Alarms and Fire Barriers

BTW is the downstairs one in the hall near the kitchen door? If it is, then IMO you'd be better with an Ei146 there (optical alarm less prone to false alrms from cooking fumes)

 

[euphoricmess]

Thanks to all that have helped so far.

I have spoken with the guys in technical support and they suggest it is faulty wiring or loose wiring to the one upstairs.

I am waiting to hear back from the electrician who did it, but as he did it a while back, and he did not install all the lights, and he seems to have some kind of injury that means he cant work, it looks like he is not going to do anything. However I am still waiting to see what happens from him before trying anything to complex with the wiring.

Just know if i try something then he comes he will just blame me when in fact its a fault he has made.

Thanks for all help, any further help is appreciated, you think writing the final bit of your PhD is stress enough, but its nice to have additions to top the stress levels up.

Thanks

G

 

[Octopus]

One of my customers had a similar problem last week, the units had been in for about 3 years then the problem. A gentle vacuuming seems to have done the trick.