Replacing old fire alarm detectors

[Sarah_W]

I want to replace both a heat detector and smoke detector in my flat. The detectors are linkd to a central system for the building and all flats. I've managed to disable this for the change and having boughtnew ones from Screwfix, took the covers off the old ones to find the attached. The Screwfix ones come with no instructions, so I'm guessing that all detectors have a standard 4 connection wire fit. If so, how do I know what wires to connect to what with teh new unit?

[Simpo Two]

Sorry, no idea - but if this is part of a system that affects other properties, should you be tampering with it?

[MonkeyHanger]

Simpo Two said:

but if this is part of a system that affects other properties, should you be tampering with it?

Simple answer. No.

If you've only removed the heads and the connections are still intact on the base, the best (and only) advice i will give is put them back sharpish and plead ignorance if someone turns up trying to find a fault.

[PistonReg]

MonkeyHanger said:

Simpo Two said:

but if this is part of a system that affects other properties, should you be tampering with it?

Simple answer. No.

If you've only removed the heads and the connections are still intact on the base, the best (and only) advice i will give is put them back sharpish and plead ignorance if someone turns up trying to find a fault.

I third that... the fire alarm systems are complex and each one will be different, so it's not going to work just plugging in some "random" detectors that you happen to have found in a catalogue :-O

[maser_spyder]

I fourth it.

I've got a couple of HMOs with fully fitted fire alarms.

If you change anything, it has to be checked, tested, and signed off for obvious safety reasons.

Given changing the heads over only takes 10 minutes, and you'll have to get them signed off anyway, get a pro in to change them.

I've taken mine off and re-fitted when we renovated, but still had the whole lot fully tested once the place was finished and tenants due to move in.

[Sarah_W]

I meant I disabled the detector region for my flat. I met tehguy who services it each year and he knew less abot it than I did and he was fine with me replacing the sensors. He said they're all standard for heat and smok and it was him who showed me how to disable my flat sensors in order to change them without setting the building alarm off.

Only prob is that the new ones don't have instrucitons. They've got 4 connections and two are spanned by a diode so I can work out what wres to coenct theseto from the existing ones, it's just the other 2 I'd like to work out insteadof jus doing it by trial and error

[maser_spyder]

Sarah_W said:

I meant I disabled the detector region for my flat. I met tehguy who services it each year and he knew less abot it than I did and he was fine with me replacing the sensors. He said they're all standard for heat and smok and it was him who showed me how to disable my flat sensors in order to change them without setting the building alarm off.

Only prob is that the new ones don't have instrucitons. They've got 4 connections and two are spanned by a diode so I can work out what wres to coenct theseto from the existing ones, it's just the other 2 I'd like to work out insteadof jus doing it by trial and error

'Trial and error'?

Even if disabled, they will still be live, disabled just means they're omitted from the system so won't trigger the alarm.

Instructions will be similar to this;

http://www.screwfix.com/prods/55127/Security/Alarm...

on the screwfix website.

However, the wiring is NOT specific to the detector, it's specific to the panel as to how it needs to be wired. Unless you have experience with the panel, you really SHOULD NOT be attempting this.

It honestly sounds like you're out of your depth, sorry.

This isn't something for amateurs. I have an Electronics degree, and would happily wire a house, or fix a telly, or pretty much anything like that. But fire alarms, no. It's a specialist thing, and should only be done properly, by a qualified person.

Just so you know, the diode should normally only be present on the final sensor in the system, which you're not going to know, because you don't have any of the original installation notes.

You should not be fitting these yourself.

HTH

[MonkeyHanger]

It is not the "Service Engineer" who gets to say who can or can not mess around with a fire alarm system. No matter how thick he may be, he's authorised to maintain & repair the system and that's as far as his remit goes.

It is actually an offence under the Health & Safety at Work act to tamper with any equipment intended for the safety of yourself or others. This includes Fire Alarm sytems (not stand-alone Smoke / Heat alarms as found in houses).

My previous advice stands. If you want the detectors changing, talk to the Service Engineer.

[hairyben]

It's unlikely what you've bought from screwfix is compatible. There are several different brands of commercial fire detector systems all of whom have several different product ranges none of which are compatible, what you are doing is probably akin to buying a brake pad for a mk2 clio and asking how you can fit it to an M5. Perhaps the morals of dicking around with a communal fire detection system to save yourself a few quid are unimportant to you but if the building management company find you tampering with it they'll probably tear you a new one, worst case scenairio is of course you in court on manslaughter/murder charges.

[Wings]

MonkeyHanger said:

It is not the "Service Engineer" who gets to say who can or can not mess around with a fire alarm system. No matter how thick he may be, he's authorised to maintain & repair the system and that's as far as his remit goes.

It is actually an offence under the Health & Safety at Work act to tamper with any equipment intended for the safety of yourself or others. This includes Fire Alarm sytems (not stand-alone Smoke / Heat alarms as found in houses).

My previous advice stands. If you want the detectors changing, talk to the Service Engineer.

Agree, if a leasehold flat, talk to the Management Company, for there are very serious Health & Safety issues you need to consider, should an incident ever takes place.

[Sarah_W]

Yikes... Glad I learnt how to add a socket spur and add recessed lighting to my bathroom and not ask here or else I might have got as many lectures on electrical work ;-)

FOund this really useful:
http://www.screwfix.com/prods/55127/Security/Alarm...

In the end, the 2 black wires went together and just had to work out which of th red was the positive and which was the negative. All fixed now and they work well... it's actually dead simple and the new ones look nice and shiney and no doubt far safer than the ageing ones that were there

Thanks,
S

[VX Foxy]

Did you use optical or ionisation smoke detectors?

[Wings]

I have the ability to carry out many differing electrical installations and repairs, but as a landlord I have the legal requirement of having to commission those installations/repairs through a fully qualified electrical contractor, particularly within a bath/shower room. For me, the risks and repercussions of a tragic incident are just too great for me to take.

Some 6 years ago a multi let property of mine, which at the time was let to 5 students, had a fire, resulting in not only sever to the property, but 2 students having to be hospitalised. The fire started at the consumer box, with 2 wires arcing as they entered the box, resulting in a flash back along electrical wires further into the property.

Both the Fire Brigade and lost adjusters for my insurers carried out a fire investigation, possibly the former looking for misuse of electricity, the latter looking to see if a poor DIY electrical installation/works had resulted in the fire. Fortunately through my retention of the electrical contractor’s invoice, and their certificate supporting the installation (new consumer box) of the same, for claim for damages etc. etc. was paid in full.

To conclude, even in one’s home, one needs to be extremely careful what electrical work a DIY person carries out, and even more who one tells about those works.

[MonkeyHanger]

VX Foxy said:

Did you use optical or ionisation smoke detectors?

Fixed temp or rate of rise heat detectors ?

Apparently it's "simple"

[VX Foxy]

MonkeyHanger said:

VX Foxy said:

Did you use optical or ionisation smoke detectors?

Fixed temp or rate of rise heat detectors ?

Apparently it's "simple"

Indeed.

[Busamav]

MonkeyHanger said:

VX Foxy said:

Did you use optical or ionisation smoke detectors?

Fixed temp or rate of rise heat detectors ?

Apparently it's "simple"

Only if you care not for the safety of the other occupants within the block .

[maser_spyder]

Let hope for Gods sake there's never a fire, or the OP is in some very, very hot water indeed.

I know what I'm doing, but would never play with the fire alarm system.

If you do this, you're an idiot, nothing more to say.

[Dr_Gonzo]

maser_spyder said:

Let hope for Gods sake there's never a fire, or the OP is in some very, very hot water indeed.

I know what I'm doing, but would never play with the fire alarm system.

If you do this, you're an idiot, nothing more to say.

Exactly. Playing with a linked fire alarm in a block of flats borders on a criminal offence.

[Dr_Gonzo]

Sarah_W said:

Yikes... Glad I learnt how to add a socket spur and add recessed lighting to my bathroom and not ask here or else I might have got as many lectures on electrical work ;-)

FOund this really useful:
http://www.screwfix.com/prods/55127/Security/Alarm...

In the end, the 2 black wires went together and just had to work out which of th red was the positive and which was the negative. All fixed now and they work well... it's actually dead simple and the new ones look nice and shiney and no doubt far safer than the ageing ones that were there

Thanks,
S

You do realise that any electrical work has to now be carried out by a 'competent' person under Part P of the building regs? Are you hoping to rent or sell this PH built flat?

[kellys hero]

Dr_Gonzo said:

maser_spyder said:

Let hope for Gods sake there's never a fire, or the OP is in some very, very hot water indeed.

I know what I'm doing, but would never play with the fire alarm system.

If you do this, you're an idiot, nothing more to say.

Exactly. Playing with a linked fire alarm in a block of flats borders on a criminal offence.

In the worst case scenario this would in all likely hood lead to the OP being prosecuted. Under article 13 of the fire safety order a competent person must undertake firefighting and fire detection measures. This is were it gets interesting...

"a person is to be regarded as competent where they have sufficient training and experience or knowledge and other qualities to enable them to properley implement the measures referred to"

Now the OP clearly isn't any of the above, the landlord would therefore not ask, or presume that a tennant would undertake this (no doubt it is in the contract any way not to interfere with such items) as he would have a certified company (now the competent person) in to conduct annual testing, repairs etc. provided he can prove this (invoices, maintainance schedules etc)and it became aparent that modifications/ replacements were down to the tennant I would imagine that the Landlord would not be prosecuted but the "tennant" would, leaving the tennant to prove that she were competant when in court.

Of course, just my opinion.