fault finding on fire alarm

[shedi123]

Afternoon, can anyone give me some advice. I'm going to have a 2nd look at a fire alarm on monday which has detected a detector fault on one of the zones. I have reset the system but the alarm will resound about 20 seconds after reset. Am I right in saying that the detector that triggers the system will have a constant red led or flashes very fast? I'm told it was triggered from a flat which till now I haven't been able to access. what are any potential problems and can I over ride the system to test by shorting out cables in the detector. thanks

 

[breezer]

if it in a bunch of flats an you are asking what to do, i would ask are you competant to do the job and more to the point are you insured?

 

[shedi123]

yes fully insured and i am a spark. I just know very little about fire alarms. So there is a detector that has triggered the alarm and it won't reset after pressing the reset button. So is the detector faulty? Can i bridge the circuit to establish that it is the detector in question that has the problem???

 

[Atilla]

yes fully insured and i am a spark. I just know very little about fire alarms. So there is a detector that has triggered the alarm and it won't reset after pressing the reset button. So is the detector faulty? Can i bridge the circuit to establish that it is the detector in question that has the problem???

I'd check your insurance again - very carefully.

 

[mattylad]

I dont suppose you know the make & model of the fire alarm panel and what the detector is?

AFAIK The circuit could be an old analogue one or may be a newer addressable one depending upon what the panel is.

You should be able to remove the device & it should bring up a fault, not set the alarms off, but it all depends upon the panel.

Need more info.

 

[breezer]

as atilla says.

fire alarms do not work how you think they do.

also as mattylad points out, more info is required, which you do not have, fire alarms have come on a long way

 

[shedi123]

Insurance is not my problem nor what i have asked about.
Yes i understand you'd need more info. I'll check it out Monday as i don't know what it is to be honest.
Thanks matty

 

[mattylad]

The reason that I need more info is that I design PCB's for them for a large PLC so should be able to get any required info from our service dept

(Basically ask them the same questions coz "I know nothing" lol

 

[kensplace]

I just know very little about fire alarms

So dont put peoples life at risk by messing around with something you dont know about, and hire a pro to do it. Even if you think you got it working, you wont know for sure, as you are not familiar with them sufficiently enough to know for sure you are not going to put lives at risk.

 

[RF Lighting]

I have to agree here.

I don't often discourage people from DIYing, an I'm all for a tradesman expanding their knowledge base, BUT, peoples lives rely on a properly functioning fire alarm.

One simple mistake, which you may not realise you have made, could leave all or part of the system not working properly, even if the panel appears to be in a healthy state.

I have repaired plenty of fire alarms after botched attempts by people who did not know what they were doing.

I was properly trained on how to install and maintain fire alarms alongside people who did know what they were doing. They are more complicated and alot more important than standard mains wiring, and there are some big differences such as cable types and jointing techniques.

There are also lots of different types of system, which you need to be familiar with all of them, and able to identify which type of system you have before you even start working on it.

 

[mattylad]

And.... there are also lots of fire alarm systems out here that are so old & bad that they need ripping out & replacing immediately, yet they still get a fire certificate because they sound sound the bells. My father had one in his hotel which was basically a relay in a box, still got a certificate.

A big problem is that many places do not have them under maintenance contact because the owner considers it too expensive & wont call a proper company out because the cost for the call out would also be what they consider excessive, which is why they call on the services of a sparky.

I'm sure that the OP if finding that it is something more than he can handle safely will be telling the owner to get a fire alarm engineer in instead.

The complexity of the system can only be ascertained by finding out what its main panel is, who knows it may be a relay in a box, part of a security alarm or even the latest addressable 2 wire system - we wont know till the OP returns.