Does a Modern Car Exhaust System Impact a Carbon Monoxide Detector's Accuracy?

[jlcd]

https://www.amazon.com/dp/B004Y6V5CI/?tag=pfamazon01-20

I bought the above carbon monoxide detector out of curiosity.. it has over 1,500 positive 5 star reviews. I put it near the exhaust in the mall parking and sit inside for 20 minutes.. but it doesn't seem to detect any carbon monoxide coming from the exhaust. The car is a Honda CRV. Does modern exhaust system have so called catalytic converter that produce almost zero output or is the detector just not accurate enough? But it's supposed to be sensitive to detect minute amount of carbon monoxide. The unit self test seems to work.

 

[Bystander]

Threshold detection limit is ppm; translates as 5-10 ppm.

 

[jlcd]

do you mean the threshold detection limit of the car or the detector?

 

[Bystander]

Root word: "detect." The automobile doesn't "detect" anything.

 

[Greg Bernhardt]

I actually have this model in my basement. The min detection is 70 ppm. Perhaps it never it never reached that amount.

 

[russ_watters]

If combustion is good, there should be little to no carbon monoxide. I remember sticking a combustion gas analyzer up the tailpipe of my car to test it (the analyzer) and I think I was getting single digit ppm readings.

 

[jlcd]

I actually have this model in my basement. The min detection is 70 ppm. Perhaps it never it never reached that amount.

how do you test if the device is working? A quick limited source of carbon monoxide...

 

[Greg Bernhardt]

how do you test if the device is working? A quick limited source of carbon monoxide...

Hit the test button and hope regulations insure it works. Kiddie is a well known brand. I wouldn't worry. You should have a carbon monoxide alarm on every house level.

 

[bigfooted]

how do you test if the device is working? A quick limited source of carbon monoxide...

... an open fire in your backyard? the exhaust of a domestic boiler when run at maximum power? Most commercial appliances that burn gas are actually quite 'clean' in the sense that they do not produce a lot of CO and NOx, so if you want to test this you should go for an uncontrolled/unoptimized fire like a fireplace, a wood stove or a basket fire (? is it called this? You have an iron basket filled with wood and burn it in your yard). The exhaust of a fireplace produces CO in the order of 1000's, but if all works well, you can only measure this at the end of the chimney.

Fun idea: go to family/friends with a fireplace and scare them witless by measuring the CO levels in their living room. It's not just fun, you could save lives as well..

 

[jlcd]

I read this in amazon "Though I can't tell how accurate it is, I can confirm it detects CO. It was reading 0 in my apartment then I put it in a large pot with a candle in it. I closed the lid and allowed the candle to burn up all the oxygen and begin creating CO. When I took it out it was reading 132 and over the next few seconds rose up to a peak of 153 before going back down to 0.

The alarm is quite loud and should be able to be heard throughout a small to medium sized house."

Is it true if the oxygen in the air is burned up.. what is left is CO? What is the chemical reactions involved?

 

[Borek]

Is it true if the oxygen in the air is burned up.. what is left is CO?

Not exactly. It rather means when there is not enough oxygen burning produces monoxide instead of dioxide.

 

[Bystander]

... or, suboxide.

 

[Ronie Bayron]

https://www.amazon.com/dp/B004Y6V5CI/?tag=pfamazon01-20

I bought the above carbon monoxide detector out of curiosity.. it has over 1,500 positive 5 star reviews. I put it near the exhaust in the mall parking and sit inside for 20 minutes.. but it doesn't seem to detect any carbon monoxide coming from the exhaust. The car is a Honda CRV. Does modern exhaust system have so called catalytic converter that produce almost zero output or is the detector just not accurate enough? But it's supposed to be sensitive to detect minute amount of carbon monoxide. The unit self test seems to work.

Gasoline engine especially new versions are way efficient compared to diesel. This because less viscous fuel (HC-hydrocarbon) contains minimal carbon than hydrogen as compared to diesel. Thus, you would expect less CO emission. Further, is the car park close or open? How many cars were there? You would expect peak reading to happen may be the last mall hours where the gas accumulate if the car park was not well ventilated.

Try to catch an exhaust gas of a diesel engine by a cellophane and put it inside, if it does not read then there must be something wrong with the calibration or the sensor. I pressume that's an IR type of sensor.