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sivoodoo

Hi all,

Just had a call to fit a heat detector and a smoke detector in kitchen and hallway respectively.

Whats the cheapest mains powered option that complies with regs?;)

Any pointers on things to look out for would be greatly appreciated,

Thank you.

Si.
 
Hi all,

Just had a call to fit a heat detector and a smoke detector in kitchen and hallway respectively.

Whats the cheapest mains powered option that complies with regs?;)

Any pointers on things to look out for would be greatly appreciated,

Thank you.

Si.
We wire them in 3core firecell cable or similar.Though I have also seen manufacters recommending flat3core+E. One advantage of the screened type of firecable is it can be used without an rcd. There are recommendations to their siteing.I think have to be 500mm min away from wall and same I think from light fitting ,eg fluorescent in kitchen.The present recommendation is that they should be on their own circuit. Also if your householder is wheelchair bound you might need one of those wall mounted reset jobbies.
 
Thanks for those quick responses,

So whats my cheapest option/model to go for, for an interlinked,battery back up, 1 heat one smoke?
 
You also need to ensure they are the correct distance from the different types of room.

There is info in the OSG about this but i think its

No greater than 7.5m from habitable rooms , and bedrooms no greater then 3m.

Kitchen, fit a heat and the rest fit a smoke.

But do check the OSG first.
 
Thanks for those quick responses,

So whats my cheapest option/model to go for, for an interlinked,battery back up, 1 heat one smoke?
sorry can't help you there.You are gonna have to phone round a few of your local wholesalers.Or start surfing.:D
 
hi
aico also do radio link detectors i think ther about £80-100 for a pair,just connect to local light upstairs and down, all depends on if youve got an ok route to link between levels sometimes the time they save make them worth the expense.smoke detectors cover a 7.5 m radius and i think the min coverage required is circulation areas on each level but i think it goes into more detail than that but cant remember of top of my head.
 
It depends on your council, where I live they have the iq of a lit-kat. They don't realise all points are 'individual' and thus send signals to other points if a fire/smoke/heat.

Some say must be wired in fp200/fire tough. I can understand sirens/alarm bell etc, but not call points. Some insist on mi. That's ok if in the spec (normally public buildings) but not in domestic houses.

However I would not 'tap off local light circuits' I think that is very bad practice, the smoke circuit needs to be dedicated, none rcd protected
 
However I would not 'tap off local light circuits' I think that is very bad practice, the smoke circuit needs to be dedicated, none rcd protected

Why is it bad practice?

Having smokes off the lighting circuit would be safer as if the lighting went out, it would be sorted fairly quickly, whereas if they were fed from their own circuit from the DB then its easy to miss the fact that the MCB may have tripped for whatever reason.

Even with battery back up, its easy to pull out the battery, if the detectors start to chirp through loss of power.

Seen this a few times, especially on rented properties.
 
Good points, thank you.

1. Can the Aico radio ones be used in rented properties?
2. I live in Leeds, does anyone know the nearest wholesaler to me who stock the Aico ones,

Cheers
 
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Why is it bad practice?

Having smokes off the lighting circuit would be safer as if the lighting went out, it would be sorted fairly quickly, whereas if they were fed from their own circuit from the DB then its easy to miss the fact that the MCB may have tripped for whatever reason.

Even with battery back up, its easy to pull out the battery, if the detectors start to chirp through loss of power.

Seen this a few times, especially on rented properties.

I would totally agree with you there but it seems to be a requirement for local authority housing.Building control regs allow either a well used lighting circuit or an independant circuit.However one of the stipulations is that there must be a means of "isolating power to smoke alarms without isolating the lighting" So back to square one.I'm not sure how to achieve this without an independant isolator fitted beside each smokie,in the case of using different circuits with radio link(which are incidently permitted):confused:
 
yep page 65-67 on site guide there in black and white.i think the designers get round the isolation part by saying you slide the detector out to maintain it therefore its isolated.only guessing like but somebodies invested time and money in produceing these things so i doubt theve got it wrong or someones for the high jump

but if you are hard wiring them i put double pole switch in the loft by the upstairs detector that can then isolate both with the eyesore.
 
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The cheapest option may end up being detectors with no battery back up
These then have to have a dedicated mcb so having to wire back to the consumer unit
I would make sure that whatever make you end up with.that there is battery back up allowing the use of a local lighting circuit ( which is my preferred method)
I dont think the difference in prices will make much difference for small quantities
If you were needing a couple of hundred then it may be worthwhile being price consious
BY the way Aico is my favourite
 
If we are going to split hairs, the OSG only says that there 'should' be a means of isolating without affecting the lighting and not 'must'.

It also states:

"Where all circuits are protected by RCD's there is advantage in supplying fire detection and alarms from regularly used lighting circuits."

So, in a nutshell, supplying from the lighting is fine IMO.

At least its better then no S.D.'s at all.
 
We wire them in 3core firecell cable or similar.Though I have also seen manufacters recommending flat3core+E. One advantage of the screened type of firecable is it can be used without an rcd. There are recommendations to their siteing.I think have to be 300mm min away from wall and same I think from light fitting ,eg fluorescent in kitchen.The present recommendation is that they should be on their own circuit. Also if your householder is wheelchair bound you might need one of those wall mounted reset jobbies.
edited
 

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