Alarm box sounding..Help!

[PNH]

I have a Gardtec 500 Series system, which I don't use, but it's been sitting here doing nothing for the past five years. Tonight the external bell box sounded off out of the blue, for quite a long time (probably about 15 mins), but there was nothing happening inside the flat, no buzzer, etc. The setting panel shows "Un", which I imagine means it is "unset".
The bell box is a plain opaque white plastic cover, a sort of triangular shape with bottom two corners squared off, no visible name. There are red lights flashing in both the bottom corners now.
Does the fact that only the external bell sounded suggest that the battery in there needs relacing, or is it likely to be something more sinister?
If it's the battery, is it a straighforward job to replace, or will I need to call out an engineer.
There was no handbook here when I bought the flat, but I was given the setting code. I've checked out a handbook online, but it doesn't say anything about this problem.
Thanks in advance for help folks.

 

[John45]

It is most likely a tamper fault with the external bell box.
This would cause an activation even if the alarm was unset.

The bell box may have worked loose if the plugs holding it on have worked loose. (soft mortar / wind and rain over time)

 

[PNH]

Thanks John, I'll check it out in the morning to see if that's the cause. If that is the cause, is it likely to sound off again before I get to it in daylight? I don't want to be waking everyone in the block all night long.

 

[John45]

Thanks John, I'll check it out in the morning to see if that's the cause. If that is the cause, is it likely to sound off again before I get to it in daylight? I don't want to be waking everyone in the block all night long.

Hopefully it won't have gone off again for you.

Bell boxes have two tamper switches usually. One to detect the whole assembly being removed from a wall or one to detect the cover being removed.

Over time the wall plugs can become less secure and the boxes tamper switch spring can push the box slightly from the wall. The tamper springs themselves can also weaken until they can't hold the microswitch down.

High winds can also create a tamper condition if the cover is not fully secure.

 

[PNH]

Thanks again John. is there a special routine I should use when investigating to avoid a "lock out" situation, or can I just go ahead and take the cover off to investigate?

 

[scott1980]

Unless the bell box tamper circuit has been bypassed/disconnected at the control panel, I would be surprised if it's the bell's tamper switches at fault. This would indicate at the control panel, unless as above, they've been disconnected.

It's more likely that the cable to the sounder has developed a fault, or there is a fault inside the external sounder.

It's not probable that it will sound again as it seems to have "timed out", but that's not to say it won't.

Unless you have a multimeter and a basic knowledge of alarms, it could be tricky trying to find the fault if it's not immediately obvious. If you don't use the alarm, now may be a good time to disconnect it, or get it serviced/checked over by a proper alarm technician.

 

[Atilla]

Unless the bell box tamper circuit has been bypassed/disconnected at the control panel, I would be surprised if it's the bell's tamper switches at fault. This would indicate at the control panel, unless as above, they've been disconnected.

It's more likely that the cable to the sounder has developed a fault, or there is a fault inside the external sounder.

It's not probable that it will sound again as it seems to have "timed out", but that's not to say it won't.

Unless you have a multimeter and a basic knowledge of alarms, it could be tricky trying to find the fault if it's not immediately obvious. If you don't use the alarm, now may be a good time to disconnect it, or get it serviced/checked over by a proper alarm technician.

told them that this morning but DFS got it pulled - he really doesnt have the first idea about systems.

 

[John45]

Unless the bell box tamper circuit has been bypassed/disconnected at the control panel, I would be surprised if it's the bell's tamper switches at fault. This would indicate at the control panel, unless as above, they've been disconnected.

It's more likely that the cable to the sounder has developed a fault, or there is a fault inside the external sounder.

It's not probable that it will sound again as it seems to have "timed out", but that's not to say it won't.

Unless you have a multimeter and a basic knowledge of alarms, it could be tricky trying to find the fault if it's not immediately obvious. If you don't use the alarm, now may be a good time to disconnect it, or get it serviced/checked over by a proper alarm technician.

You are correct . My suggestion was only one of a number of possibilities , The OP has said it hasn't been used for many years so there could be many problems with the system.

 

[Atilla]

Unless the bell box tamper circuit has been bypassed/disconnected at the control panel, I would be surprised if it's the bell's tamper switches at fault. This would indicate at the control panel, unless as above, they've been disconnected.

It's more likely that the cable to the sounder has developed a fault, or there is a fault inside the external sounder.

It's not probable that it will sound again as it seems to have "timed out", but that's not to say it won't.

Unless you have a multimeter and a basic knowledge of alarms, it could be tricky trying to find the fault if it's not immediately obvious. If you don't use the alarm, now may be a good time to disconnect it, or get it serviced/checked over by a proper alarm technician.

You are correct . My suggestion was only one of a number of possibilities , The OP has said it hasn't been used for many years so there could be many problems with the system.

you are aware of the regulations relating to the "fixing of bellboxes to the fabric of the building...." aren`t you?

 

[PNH]

Thanks all for the info. Hope I haven't caused friction amongst some of you here....
I've bitten the bullet and arranged for a professional (I hope!) to pop round on Friday to take a look at it and hopefully sort it. I'll report back with outcome, just for info. Thanks again.

 

[Atilla]

Thanks all for the info. Hope I haven't caused friction amongst some of you here....
I've bitten the bullet and arranged for a professional (I hope!) to pop round on Friday to take a look at it and hopefully sort it. I'll report back with outcome, just for info. Thanks again.

Gardtec 500 -

it`s a good little panel but a bit dated and will probably need a new back up battery - if they try and write the control unit off (and dont let em con you with a wireless upgrade - thats anything but) dont be scared to get a second opinion

External sounder -

probably needs changing but we wouldnt be expecting to do much more

 

[PNH]

Thanks mate. Good advice.

 

[PNH]

Just for info. It was a fault in the external bell box. Could have been fixed, but probably cheaper to replace it at approx £100, and the internal battery needed replacing (it was 13 yrs old!). Sacreligiously I decided not to do it and just had the whole thing disconnected since I never use it. That was expensive enough! Many thanks to everyone for all the helpful comments.

 

[Atilla]

thanks button is -------------------------------------->