LPG Gas detector

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kiwijunglist

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#280479 17-Dec-2020 08:00

I let my wife have a gas hob against my better judgement, because she does most of the cooking. I wanted an induction hob. She keeps accidently leaving the gas running when we go out / overnight.

Does anyone know the best model for an LPG leak alarm that has a low threshold, I want to mount in near the hob so it goes off if the gas is slowly leaking. I think the chance of an explosion is probably fairly low because we have an open plan kitchen, but there have been several times when I have either got up in the morning or got home from being out to find the gas is running on the stovetop. I think she turns it off then turns it past off and back to on again.

Ideally I'd like to buy a gas detector where the detector is on a lead so I can please it low on the bench near the stovetop (LPG is heaver than air).

Mike

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#2623089 17-Dec-2020 08:02

Put a photo of this gas explosion up somewhere as a reminder.

dklong

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#2623096 17-Dec-2020 08:14

They are very common on boats so perhaps try your nearest Chandlery (eg Burnsco or similar).

https://www.burnsco.co.nz/shop/safety/gas-detectors/natural-gas-lpg-detector

Some will even turn the gas off if a solenoid control is fitted to the bottle (which is s good way of turning the gas on/off remotely).

Fred99

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#2623124 17-Dec-2020 09:34

As far as boats and caravans go they *were quite expensive (not as expensive as having your boat or house blown to smithereens of course) and as the detector component has a (very low current draw) heater element that they've got a finite life, a couple of years perhaps. Mine takes about 5 minutes to "warm up". I check the one on our boat regularly - there's enough gas pressing the button while holding a disposable lighter close without lighting it to trigger the alarm when held close to the detector. They're not particularly selective, petrol vapour or solvents will set them off (but that's a good thing).

*I see Burnsco have one 12v model for sale for $70 - a few years ago they were 3x that price.

shk292

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#2623125 17-Dec-2020 09:36

dklong:

They are very common on boats so perhaps try your nearest Chandlery (eg Burnsco or similar).

https://www.burnsco.co.nz/shop/safety/gas-detectors/natural-gas-lpg-detector

Some will even turn the gas off if a solenoid control is fitted to the bottle (which is s good way of turning the gas on/off remotely).

Those BEP ones are fitted to nearly every yacht I've sailed and work perfectly.

Fred99

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#2623128 17-Dec-2020 09:52

kiwijunglist:

I think she turns it off then turns it past off and back to on again.

Has it got flame failure protection?
https://www.ewrb.govt.nz/about-us/news-and-notices/flame-safeguard-on-gas-appliances-certified-to-asnzs-5263-1-1/

(I'm very surprised - it doesn't seem mandatory in NZ)

kiwijunglist

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#2623129 17-Dec-2020 09:54

It don't think it does. I think it's not flame failure though it's turning the gas on after it's been off but not igniting it.

It's quite an expensive stove top from AEG, it was more expensive than all the other 75cm options too.

Edit

It does have flame failure but I guess that is different to just turning the stove top on without igniting it.

https://www.aegnewzealand.co.nz/cooking/cooktops/hg75fxa/

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gbwelly

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#2623130 17-Dec-2020 10:00

kiwijunglist: It don't think it does.

Test it, I've never encountered one that continues to supply gas if the thermocouple doesn't detect a flame, and the usual start procedure is no gas without manually depressing the knob, only then once it's running the knob can be released.

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Fred99

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#2623135 17-Dec-2020 10:12

Here's a domestic (230v) gas detector:

https://clyne-bennie.co.nz/product/gas-detector/

Good to see that price is coming down, and that model comes with a 3 year warranty and claimed 5 year sensor life (in continuous use).

jasonbug

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#2623154 17-Dec-2020 10:47

gbwelly:

kiwijunglist: It don't think it does.

Test it, I've never encountered one that continues to supply gas if the thermocouple doesn't detect a flame, and the usual start procedure is no gas without manually depressing the knob, only then once it's running the knob can be released.

Gas ovens/elements without the flame shutoff are more common than you think.
It does seem light an oversight not passing regulation to ban new ones going in.

kiwijunglist

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#2623166 17-Dec-2020 11:07

I rang AEG and they said it shouldn't be possible for it still to have gas going without a flame so they have me the number of their service agent.

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kiwijunglist

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#2623292 17-Dec-2020 14:42

Hmmm

It has a thermocouple connected to each solenoid valve that is functioning correctly. I checked each valve on every element, you can't start the gas flowing unless you press down on the igniter and the gas solenoid correctly shuts off when you extinguish the flame and the thermocouple gets cold.

It did happen on a warm day, I wonder if the temperature threshold of the thermocouple is a bit low, eg. like 25C or something like that.

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elpenguino

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#2623375 17-Dec-2020 16:53

kiwijunglist:

Hi

I let my wife have a gas hob against my better judgement, because she does most of the cooking. I wanted an induction hob. She keeps accidently leaving the gas running when we go out / overnight.

Just a long shot but, does your wife watch lots of Agatha Christie mysteries?

Have you noticed your tea tastes of almonds by chance?

Most of the posters in this thread are just like chimpanzees on MDMA, full of feelings of bonhomie, joy, and optimism. Fred99 8/4/21

andrewNZ

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#2623414 17-Dec-2020 19:13

The temperature for the thermocouple will be hundreds of degrees not tens of degrees.

Is it one that you have to press down to turn from the off position? Can it be slightly on and hold itself down?

Is it possible something is being left on the knobs holding them down?

kiwijunglist

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#2623509 17-Dec-2020 22:09

I don't think there was anything holding down the knobs, but you are right if the Thermocouple/solenoid is not malfunctioning you would think that would be the only way.

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gzt

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#2625118 21-Dec-2020 21:52

dklong:

They are very common on boats so perhaps try your nearest Chandlery (eg Burnsco or similar).

https://www.burnsco.co.nz/shop/safety/gas-detectors/natural-gas-lpg-detector

These all are 12V marine/automotive supply. Adapters DIY

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