Ei 151 Beeping

[Guest]

My enquiry concerns a mains powered smoke alarm Ei151TL. The electricity was off for a while and since it has been switched back on the alarm beeps every few minutes. At first I assumed it was because it was recharging but it has now been days. The green light indicating that it is connected to the mains glows. Please could you advise? Can the batteries be replaced on this model? Or would I need to replace the whole unit? Is it just a case of holding down the test button for a while?

[Garry Webster]

The Ei151TL is a sealed unit so the batteries are not replacable.

The 151TL will emit this beep for 2 reasons:

-1. Mains power was lost and the back-up batteries have run down, but the unit will recharge
-2. The unit is in "hush" mode, these beeps will self-cancel after ten minutes just by doing nothing

It sound to me like none of the above have happened in your case. Can you tell me how long you have your alarm it may be the it has come to the end of its working life and needs replacing or it may be that you have the older Ei151 alarm?

Kind regards Garry

[Guest fredgardner]

My Ei151TL is beeping continuously! How do I stop this??? It drives me crazy

[Safelincs]

Hi

You might have an older model with alkaline backup batteries which must be replaced regularly (eg once a year). Open the alarm cover and replace the battery.

If the alarm continues bleeping your mains power might be interrupted. If the green light is off, you have no mains power and the smoke alarm now consumes the backup battery. Check your fuses, circuit breakers and wiring.

If the green light is on, however, try to reset the alarm by pressing the test button for more than 10 seconds to reset the alarm.

If nothing else helps, replace the smoke alarm (All smoke alarms should be repalced after ten years!)

How to remove a Ei151 alarm

Replacement alarms for Ei151

Harry

[Guest NormHast]

Hi

I am getting confused. My old smoke alarm model states Ei151TL but on your website you only sell Ei151. What is the difference and will the new unit fit?

Norm

[Safelincs]

When the Ei151 was orginally produced in mass production there were several models (alkaline battery, lithium battery with/without hush). You can replace all of them with the easichange replacement model. Please keep in mind this is a job for an electrician. The new units will communicate correctly with any remaining EI150 alarms in your system.

Harry

[Guest Neil]

Thanks Harry, holding the test button in for more than 10 seconds reset the detector and it stopped beeping :)

I had only pressed it for about 2 seconds beforehand it then every 40 seconds it beeped.

[Guest MartinGof]

On a similar topic I was wondering whether anybody could help me.

I have recently installed (July) some new ei151 alarms to replace older versions of the same alarm.

The old alarms had been randomly setting off - no smoke/dust and mains power on - and so I decided to replace them.

This morning the new alarms have been randomly emitting short (1-2 seconds) alarm sounds. No evidence of smoke/fire or any problems. Why are they doing this? Is this a signal to say they need testing?

Help!

[Safelincs]

Hi Martin

have you checked that the mains power supply is permanently on? If the power supply is taken from an incorrectly installed lighting circuit that can be interrupted by a switch this could cause this type of low battery warning. Check that the green light is on all the time indicating power supply.

If the power supply is directly from the fuse box make sure the fuse has been switched on again after the smoke alarm replacement (honestly, this happens quiet often!)

Harry

[green-foam]

Following on from what Harry said, what happens if you switch the lights off (at the switch) in a room where the smoke alarm is. Does the "mains on" light go out after say 2 minutes.

[Guest Amanda]

Hi,

We have an ei 150 which has started beeping this am (been going for about 3.5hrs so far and driving me crazy!!) there has been no power cut, they are connected to the mains and have a green light and tere is no battery to replace according to the back of the alarm. We have tried holding the test/hush button for 10 seconds and it does nothing (except setting the actual alarm off!)

We have come to the conclusion they need to be replaced (we think they are about 11-12 years old) however, the problem is the beeping won't stop!!! We have turned the main power supply to them off, taken the units from the ceiling and switched them off at the dedicated plug, yet they still beep!! (It's like phoebe from friends' experience!!) how can I get them to be silent while we await the replacement ones. I am a nurse on night shifts so this beeping for a few days is NOT an option!!

Thanks for your help in advance!!

Amanda

[Safelincs]

Hi Amanda

The units should stop beeping once they are off the ceiling. Sometimes there is a residual charge that makes the alarm been for a few minutes. It should be possible to stop this by pressing the test button in the middle. Could it be the other alarms in the circuit making the beeping noises? They should ideally all be removed from the ceiling and be replaced.

The Ei150 replacement is the Ei151EK easichange alarm.

Harry

[Guest Amanda]

We took both alarms off the ceiling, and they were definitely beeping for a few minutes, hence we put them back up! Will try again this evening! Thanks for your help :-)

[green-foam]

Watching the video, the detector DOES have a battery inside.

I guess this is almost / nearly flat and that is why the unit is beeping.

Although the battery is not meant to be changed, I wonder is there a link that can be removed to disable the battery?

It LOOKS LIKE the "outer cover" can be unclipped and swung open

(I did note it says "do not open unit" but in this case you don't seem to have much choice)

[Guest norman cleary]

I have the same issue. The power was off for about 10minutes and now the unit is bleeping. My question is how long does this last? The outside of the unit says it needs replacing in 2020.

[Bob.G]

Hi all. First time here and looking for help please.

We had a power spike and blackout for about 15 minutes three days ago and since then one of our two interconnected EI151 detectors have been beeping, and the other just 'chirps'. I had a look online for help and found this site - I've read all the posts and done as suggested above to no avail. With the power to the units off I removed the head that was chirping and noted that the four wires (blue, blue, red, yellow) were not on a plug but soldered into position with an insulating sleeve. I assume that the other one will be the same. Note that the units do not carry a date but are believed to be about 20 years old.

Query 1: Do the replacement units come with a plug that accepts cable terminations to enable me to replace the unit, or will I need to resolder the connections ?
Query 2: How do I determine which of the two blue cores to connect to the 'battery' terminal (I'm assuming that red = live and yellow = 'interconnect').

[green-foam]

The new units should come with a plug, I would guess that the original plug was lost and so some one soldered the wires on instead.

I am puzzled why you mention The "battery terminal" since mains powered smoke alarms are connected as follows.

Live, Neutral and "interconnect" This is repeated at every detector.

Since you will be replacing all 3 I would suggest you check (with a multi meter) at the first one which colour does what, since there are no strict guidelines for the colours, and then copy this colour code with all the detectors.

[Guest bob.g]

Green-Foam, thanks for the response.

My EI151 has 4 terminals, (Live, Battery, Interconnect, Neutral). I'll check the voltages on each line and work out wht to do.

I'll be back !

[Safelincs]

Hi Bob

10 to 20 years ago there was a change in the Ei150 series smoke alarms. The older units had connector plugs with 4 evenly spaced holes or just 3 holes.

The newer units since then have 4 holes in the connector plug with 3 holes grouped closely together and the 4th one slightly apart.

There are replacement alarms for the Ei150 series (Ei150, Ei151, Ei151TL, Ei154, Ei154TL, Ei156, Ei156TL). You will need to change the plate and connection but the alarm will communicate with any other Ei150 alarms in the system and the kit comes with a plate to cover any blemishes on the ceiling from the old rectangular Ei150 alarm.

Harry

[alarm]

We had these alarms installed in every room of our house after the loft conversion was done 1.5 years ago. Last night at 2am all the alarms went off and then stopped suddenly before we got to press the button. No trigger found. It scared the life out of my children and we couldn't sleep for the rest of the night worrying about them doing this again. I can't find a reason why this happened. They are still new and don't need replacing till 2020(says on the alarms) and batteries are not replaceable. They were all installed by a qualified electrician and it's never happened before. Any idea why this happened and how to make sure this nightmare will not happen again?

[Safelincs]

Hi, that sounds like a very stressful situation and needs sorting quickly. I suggest you speak with AICO's helpline 01691 664100

It could just be an insect in a detection chamber but whatever it is it is best in this case to speak directly with the manufacturer.

Harry

[green-foam]

I would add have you considered the fact the smoke alarms were doing their job?

A smoke alarm will make its alarm noise for as long as it detects smoke or similar sized particles, when the smoke or similar has cleared the detector will stop, just as yours did.

As you have interlinked detectors (which is good) when one sounds they all sound. I suggest that one of them detected a small amount of smoke or similar.

If they do this again, or on a regular basis then you would need to make logs of what time who was where etc, but as it was just a one off I would not worry about it, since if it was smoke or similar, you did not notice it, but then, were you looking for it?

[Tom Sutton]

You didn’t say if they are domestic smoke detector and are interconnected, I will assume they are domestic smoke detector connect to the mains, if so you first need to know how they work so check out http://www.explainthatstuff.com/smokedetector.html to give a basic understanding.

As you can see there are two circuits the sensor circuit and the alarm circuit. If the sensor circuit had triggered the alarm any contaminate in the sensor chamber would most probably remain and the alarm would have gone into full alarm. However if the alarm circuit had been stimulated by such as a spike on the electricity supply this might operate the alarm for a short period of time. It may also apply if it is an A, B, or C category of fire alarm but do understand isolating cause of false alarms is notorious difficult exercise.

[green-foam]

No offence to Tom, but I suggest to anyone reading this ignore what that website says, It has miss-information on several articles, how a smoke detector works being one of them.

Optical smoke detectors do NOT work by smoke breaking a beam. The opposite is infact true.

Inside an optical smoke detector is an infra red LED and an Infra red receiver.

The Infra red LED does emit Infra red light, but it is NOT pointing at the receiver, the two are at right angles to each other. (See the video clip below)

When smoke enters the detection chamber it scatters the light, this is then detected by the infra red receiver, the detector then goes into alarm.

You can clearly see this layout in a commercial smoke detector, it is bigger, so easier to see, but it works the same way (Large grey object on the right, and large black "lump" on the left.)

http://www.youtube.com/watch?v=sI2Y9AhDv6k

There is a smoke detection method that relies on smoke obscuring an infra red beam, but it is to cover large roof areas, and the units are too big to fit inside a smoke detector.

[Tom Sutton]

Green-foam I agree fully with what you say but the point I was trying to make was the two circuits in a smoke detector and a spike on the power supplies may have triggered the alarm circuit for a short period, then reset. I know it is likely there is circuitry to aid suppression of voltage transients and RF interference, to reduce the chances of false alarms but maybe it failed in this case.