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CO detector

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Terry Pinnell

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Apr 26, 2009, 9:07:37 AM4/26/09
to
British Gas sold me one of those battery-operated carbon monoxide
alarms a couple of years ago. Battery is apparently not due for
replacement until 2012. But can someone please remind me:

1) What the Test button should do? Here it just illuminates a green
'Power' LED, but I'm wondering if it should also sound the alarm (as
is the case with smoke detectors)? The instructions on the back merely
say 'Use the Test button to check that the unit is working correctly'
- which is not very helpful!

2) How I could test it in practice? IOW, what is a safe temporary
source of CO that should trigger it? I tried both an unlit gas ring
and the boiler vent outside the kitchen, but neither triggered it. I
suppose a predictable source would be the exhaust from my car?

--
Terry, East Grinstead, UK

Stuart B

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Apr 26, 2009, 10:02:08 AM4/26/09
to

This article mentions the test button only testing the circuitry and
not the detector but also refers to an aerosol kit which is used to
test the alarm detector.
http://www.plumbingpark.co.uk/plumbing_hvac_article12913.html

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Stuart B

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Apr 26, 2009, 10:06:20 AM4/26/09
to
On Sun, 26 Apr 2009 15:02:08 +0100, Stuart B
<xpoz...@NOSPAMgmail.com> wrote:

>On Sun, 26 Apr 2009 14:07:37 +0100, Terry Pinnell
><terrypi...@THESEdial.pipex.com> wrote:
>
>>British Gas sold me one of those battery-operated carbon monoxide
>>alarms a couple of years ago. Battery is apparently not due for
>>replacement until 2012. But can someone please remind me:
>>
>>1) What the Test button should do? Here it just illuminates a green
>>'Power' LED, but I'm wondering if it should also sound the alarm (as
>>is the case with smoke detectors)? The instructions on the back merely
>>say 'Use the Test button to check that the unit is working correctly'
>>- which is not very helpful!
>>
>>2) How I could test it in practice? IOW, what is a safe temporary
>>source of CO that should trigger it? I tried both an unlit gas ring
>>and the boiler vent outside the kitchen, but neither triggered it. I
>>suppose a predictable source would be the exhaust from my car?
>
>This article mentions the test button only testing the circuitry and
>not the detector but also refers to an aerosol kit which is used to
>test the alarm detector.
>http://www.plumbingpark.co.uk/plumbing_hvac_article12913.html
>
>
>
>
>

Oops
Forgot the sales link
http://www.detectagas.com/how_to_buy_detectagas

Peter Scott

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Apr 26, 2009, 10:38:07 AM4/26/09
to
Terry Pinnell wrote:
> British Gas sold me one of those battery-operated carbon monoxide
> alarms a couple of years ago. Battery is apparently not due for
> replacement until 2012.


I think you'll find that its the device that must be replaced not the
battery. Mine has a five-year life, then it's into the bin.

But can someone please remind me:
>
> 1) What the Test button should do? Here it just illuminates a green
> 'Power' LED, but I'm wondering if it should also sound the alarm (as
> is the case with smoke detectors)? The instructions on the back merely
> say 'Use the Test button to check that the unit is working correctly'
> - which is not very helpful!

Should make the alarm noise. If you misunderstood the life expectancy
praps the batteries are dead? Mind you it should have sounded to show
low battery.

>
> 2) How I could test it in practice? IOW, what is a safe temporary
> source of CO that should trigger it? I tried both an unlit gas ring
> and the boiler vent outside the kitchen, but neither triggered it. I
> suppose a predictable source would be the exhaust from my car?
>


Or breath from a smoker???

Peter Scott

dtechy

unread,
Apr 26, 2009, 2:15:40 PM4/26/09
to

press and hold the button until it should sound, if not contact BG for
sdvice


--
dtechy

Al

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Apr 26, 2009, 3:25:49 PM4/26/09
to
> British Gas sold me one of those battery-operated carbon monoxide
> alarms a couple of years ago. Battery is apparently not due for
> replacement until 2012.

Unlikely. More likely the sensor will be fscked by 2012. The batteries will
be long gone I suspect.

> 1) What the Test button should do? Here it just illuminates a green
> 'Power' LED, but I'm wondering if it should also sound the alarm (as
> is the case with smoke detectors)?

I cannot imagine any situation where an "alarm test" function would not
actually test the "alarm".

> 2) How I could test it in practice? IOW, what is a safe temporary
> source of CO that should trigger it? I tried both an unlit gas ring
> and the boiler vent outside the kitchen, but neither triggered it. I
> suppose a predictable source would be the exhaust from my car?

ROFL.

Just buy a new one.

But, if you feel like *really* testing it, sit in your car in a closed
garage, hosepipe from exhaust to partially open window, start engine and
wait. SO much easier than phoning BG, buying a battery or buying a new
alarm.

;-)

Al.

Ed Sirett

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Apr 26, 2009, 4:28:50 PM4/26/09
to

I would expect that presing and holding the test button should make it
sound. If not it's defunct.

Unlit [natural] gas does not contain any significant amount of CO.
The CO from a boiler in good order is also unlikely to trigger the alarm.
A vehicle exhaust should trigger the unit.

The alarms are not a substitute for proper installation and servicing and
have little benefit except with open flues appliances or jut maybe with
flueless appliances.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

Terry Pinnell

unread,
Apr 26, 2009, 5:33:09 PM4/26/09
to
Ed Sirett <e...@makewrite.demon.co.uk> wrote:

>On Sun, 26 Apr 2009 14:07:37 +0100, Terry Pinnell wrote:
>
>> British Gas sold me one of those battery-operated carbon monoxide alarms
>> a couple of years ago. Battery is apparently not due for replacement
>> until 2012. But can someone please remind me:
>>
>> 1) What the Test button should do? Here it just illuminates a green
>> 'Power' LED, but I'm wondering if it should also sound the alarm (as is
>> the case with smoke detectors)? The instructions on the back merely say
>> 'Use the Test button to check that the unit is working correctly' -
>> which is not very helpful!
>>
>> 2) How I could test it in practice? IOW, what is a safe temporary source
>> of CO that should trigger it? I tried both an unlit gas ring and the
>> boiler vent outside the kitchen, but neither triggered it. I suppose a
>> predictable source would be the exhaust from my car?
>
>I would expect that presing and holding the test button should make it
>sound. If not it's defunct.
>
>Unlit [natural] gas does not contain any significant amount of CO.
>The CO from a boiler in good order is also unlikely to trigger the alarm.
>A vehicle exhaust should trigger the unit.
>
>The alarms are not a substitute for proper installation and servicing and
>have little benefit except with open flues appliances or jut maybe with
>flueless appliances.

Ed, Peter: Thanks, both. I'll try it alongside my car exhaust
tomorrow, and if that doesn't trigger the alarm I'll call British Gas.

Message has been deleted

Andrew Gabriel

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Apr 27, 2009, 7:17:27 AM4/27/09
to
In article <75l5f3F...@mid.individual.net>,
Huge <Hu...@nowhere.much.invalid> writes:

> On 2009-04-26, Terry Pinnell <terrypi...@THESEdial.pipex.com> wrote:
>
>> Ed, Peter: Thanks, both. I'll try it alongside my car exhaust
>> tomorrow, and if that doesn't trigger the alarm I'll call British Gas.
>
> If your car has a catalyst, it likely won't trigger the alarm. The CO is
> oxidised to CO2.

Yes, that's thrawted many a suicide attempt in the last decade.

In the interest of science, and at the cost of a slice of bread
from my just baked loaf, I decided to test something I recall
hearing many years ago (probably when I was at school), that a
toaster gives off CO.

Turned timer up to max so it doesn't stop until I want it to,
and start the toasting. No CO at all initially. Eventually
smoke starts coming out, and then the CO slowly starts climbing.
However, even with quite a bit of smoking, we're only up to
10ppm, and I doubt that's high enough to trigger a CO alarm.
Measurement done with a calibrated flue gas analyser.

Note that some CO sensor elements used in home detectors are
easily permanently poisoned by other contaminents, such as
household cleaners, etc. Blasting such a sensor with various
things to see if you can make it trigger may actually go some
way to wrecking it, and this is also why they only have a
limited life.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

dennis@home

unread,
Apr 27, 2009, 7:28:11 AM4/27/09
to

"Andrew Gabriel" <and...@cucumber.demon.co.uk> wrote in message
news:49f59447$0$513$5a6a...@news.aaisp.net.uk...


> In article <75l5f3F...@mid.individual.net>,
> Huge <Hu...@nowhere.much.invalid> writes:
>> On 2009-04-26, Terry Pinnell <terrypi...@THESEdial.pipex.com> wrote:
>>
>>> Ed, Peter: Thanks, both. I'll try it alongside my car exhaust
>>> tomorrow, and if that doesn't trigger the alarm I'll call British Gas.
>>
>> If your car has a catalyst, it likely won't trigger the alarm. The CO is
>> oxidised to CO2.
>
> Yes, that's thrawted many a suicide attempt in the last decade.
>
> In the interest of science, and at the cost of a slice of bread
> from my just baked loaf, I decided to test something I recall
> hearing many years ago (probably when I was at school), that a
> toaster gives off CO.
>
> Turned timer up to max so it doesn't stop until I want it to,
> and start the toasting. No CO at all initially. Eventually
> smoke starts coming out, and then the CO slowly starts climbing.
> However, even with quite a bit of smoking, we're only up to
> 10ppm, and I doubt that's high enough to trigger a CO alarm.
> Measurement done with a calibrated flue gas analyser.

You could have got it higher by restricting the air flow.
However it would probably catch fire or trip a thermal cut out.

John Stumbles

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Apr 27, 2009, 8:48:28 AM4/27/09
to
On Mon, 27 Apr 2009 11:17:27 +0000, Andrew Gabriel wrote:

> Measurement done with a calibrated flue gas analyser.

Are these de rigeur for Keston owners then? ;-)

--
John Stumbles

A backstreet vasectomy left me sterile

Dave Plowman (News)

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Apr 27, 2009, 8:53:34 AM4/27/09
to
In article <6u3Jl.49973$NW7....@newsfe25.ams2>,

Ed Sirett <e...@makewrite.demon.co.uk> wrote:
> Unlit [natural] gas does not contain any significant amount of CO.
> The CO from a boiler in good order is also unlikely to trigger the alarm.
> A vehicle exhaust should trigger the unit.

An older car probably would since they can be 5% CO plus. Newer ones with
cats produce less CO than the existing concentration in many areas.

--
*I didn't drive my husband crazy -- I flew him there -- it was faster

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

Andrew Gabriel

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Apr 27, 2009, 10:01:55 AM4/27/09
to
In article <75lnssF...@mid.individual.net>,

John Stumbles <john.s...@ntlworld.com> writes:
> On Mon, 27 Apr 2009 11:17:27 +0000, Andrew Gabriel wrote:
>
>> Measurement done with a calibrated flue gas analyser.
>
> Are these de rigeur for Keston owners then? ;-)

That was my original reason for buying it.
There are about about 8 gas appliances I maintain in
the family, and it's useful for them all, although if
I work out the cost per check in terms of the purchase
and calibration charges, it's probably �20/check.

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