Let's do it again: CO Detectors

AA5Bman

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He who ironically no longer flies an AA5B
Hi everyone, yes, I used the search function. Yes I googled, and yes I read the AvWeb articles. But I think I'm saturated in information at this point. Can someone just tell me where to spend my money? I'll send you my CC info hah.

I'd like to buy a CO detector for the plane that...
- Is aviation appropriate (i.e. appropriately sensitive)
- Does not have to have any daily test requirement
- Can be left "on" like a home CO detector
- Is loud enough to be heard in noise-cancelling headsets
- Is probably not panel mount, unless it is close to the budget, which I assume they are not, and...
- Is not more than, say, $200

What fits the bill?
 
As has been mentioned elsewhere, Sensorcon. I have the Industrial Pro version that has the vibrating and audible tone when warning. I fly different airplanes so I don’t leave it in the plane between flights and probably wouldn’t if it remained outside in extreme temperatures. There is always somewhere to put it (or hang it) with the movable half ring that is at the top of it.

When I first started using it I didn’t recognize the audible tone and couldn’t figure out where that tone was coming from. It was the out of site monitor! Would not make that mistake twice so I made sure to have it visible at all times.

If you can adjust your requirements slightly and turn it on before a flight or off after a flight, then it fits the bill.
 
I almost bought the sensorcon one, but I am afraid that if I have to remember to turn it on and off, it won't happen, which 100% obviates the point of buying one. I have also read that the Sensorcon one is not loud enough to be used with noise-cancelling headsets. Thus the conundrum.
 
I have the sensorcon. I leave it in the plane. I often forget to turn it off. I rarely forget to turn it on. It’s part of my instrument scan.


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I have also read that the Sensorcon one is not loud enough to be used with noise-cancelling headsets. Thus the conundrum.

it vibrates too, which works great when attached to your belt.

My thoughts: if a pilot is concerned enough about CO then they should include it in their scan. So, if you can’t here the beep, and don’t feel the vibration than you’ll see the value on the screen.
 
I almost bought the sensorcon one, but I am afraid that if I have to remember to turn it on and off, it won't happen, which 100% obviates the point of buying one. I have also read that the Sensorcon one is not loud enough to be used with noise-cancelling headsets. Thus the conundrum.
I also have the sensorcon. It's not very loud, but I can hear it wearing my Zulu's. I velcroed it on the panel directly in front of the passenger seat. The lance gets exhaust in the cabin at very high aoa, so I'll be doing slow flight or stalls, and hear it beeping. It's soft enough that it takes a second to realize what I'm hearing. It alarms at a low enough level of co though that I'm not worried about missing it due to being hypoxic.

It has been on since I purchased it two years ago. I also wanted one that I wouldn't have to remember to turn on. Iirc they advertise a multiple year battery life. Come to think of it I think it's supposed to be calibrated after two years. Need to check on that.
 
+1 Sensorconn.

Panel mount with velcro.
We've left it on several times and I donated the first one after 2yrs of use and battery was still going strong.
 
Anyone have a sense for the cost to install a panel mount version? I’m not loving the idea of velcro’ing something to my (recently cleaned up) panel.
 
I just hang the sensorcon on the primer knob when flying a Cherokee. It’s right next to the Tach so I can’t help but see it as I check the RPMs. If you are flying a Grumman you probably have several places it can be hung from. Someone near you that has one can demonstrate.
 
I have the Sensorcon. I haven't turned it off in approximately 2 years. Very low drain on the battery.
 
I'd like to buy a CO detector for the plane that...
- Is aviation appropriate (i.e. appropriately sensitive)
- Does not have to have any daily test requirement
- Can be left "on" like a home CO detector
- Is loud enough to be heard in noise-cancelling headsets
- Is probably not panel mount, unless it is close to the budget, which I assume they are not, and...
- Is not more than, say, $200

Check, on all of those!

This is the brand I've been using for years, really like it. It is sensitive (down to 10ppm), has sensible increasing alarms that can be cleared at each stage (until it goes higher), is a never turn off unit, and comes with a lithium cell that is never replaced. It times out after about five years, when it judges its sensor to be out of spec.

Keep one in my bedroom as well, in addition to the others I have at home.

upload_2021-9-18_12-47-40.png

https://www.amazon.com/CO-Experts-Carbon-Monoxide-Monitor/dp/B07KFQDLZS/ref=sr_1_38 (shows out of stock)

https://www.amazon.ca/CO-Experts-Ca...d=1&keywords=co+sensor&qid=1631983479&sr=8-38 (available from Amazon Canada, will ship to the US)

There is a newer model, but I prefer this one, and they sell both. The stand just clips on/off, you can velcro the unit to somewhere below your panel where it is visible.

You should normally be below 10ppm at cruise. During a steep climb, or taxiing you may get up to 12ppm or 15ppm. For me going above 20ppm is definitely abnormal, and going above 30ppm is a land as soon as practicable and investigate scenario. One time when that happened, I found a slightly loose exhaust riser bolt, it was after some maintenance.

Don't leave the ground without it :)

* Orest
 
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Glad to hear no one's promoting the cardboard dot any more. I think a St. Christopher medal or bobbing hula girl would be equally effective (if not more so).
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Not $200, but if you need ADS-B in, the Sentry works quite well with Foreflight/iPad. Just the other day, I was getting checked out in a Cherokee Six with a CFI and I threw my iPad in the plane with the Sentry suction cupped to the rear window. I had the CFI just hold on to the iPad and if he'd like, he could look at it while in flight (for traffic). But my thought was at least I'd be receiving audible alerts for traffic (as a minimum) and I ended up getting an audible alert for the CO alarm going off. I had been flying w/the little side window open, exhaust was apparently making it in. Closed the window and no more alarm. The audible part was pretty nice though.
 
The Forensic Detectors CO detector, just under $100, works fine. It's what I have in my plane.. What you want is a CO detector with a low threshold and short dwell time. The Forensics Detectors and Sensorcon devices meet those requirements. They are electrochemical sensors and can be left on if desired.. just replace the battery as needed, and discard when the sensor lifetime expires. The electrolyte in the detector eventually dries out. Home Detectors are hopeless, as they have very high alarm thresholds and dwell times that might exceed your flight time.
 
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Not $200, but if you need ADS-B in, the Sentry works quite well with Foreflight/iPad. Just the other day, I was getting checked out in a Cherokee Six with a CFI and I threw my iPad in the plane with the Sentry suction cupped to the rear window. I had the CFI just hold on to the iPad and if he'd like, he could look at it while in flight (for traffic). But my thought was at least I'd be receiving audible alerts for traffic (as a minimum) and I ended up getting an audible alert for the CO alarm going off. I had been flying w/the little side window open, exhaust was apparently making it in. Closed the window and no more alarm. The audible part was pretty nice though.

Now compare the CO readings on a Sensorcon or Forensics CO monitor. The CO detector on my Sentry was consistently reading 85-100 ppm, where my Forensics CO monitor regularly reads 0, or occasionally 10-15 ppm in a turn.

The only plus the full size Sentry has over the Sentry mini is the rechargeable internal battery. The CO alarm and the faux-ADHARS are worthless.
 
I’ve owned 4 coexperts units over a 15 year or so period. I wouldn’t buy any other brand.. I tried the sensorcon and promptly returned it. I forget the multiple reasons but remember the most important one, it was extremely quite and almost impossible to hear. I then bought this one and it is perfect..

http://coexperts.ca/product/model-pg-2017/
 
PS.. The coexperts unit was sensitive and consistent enough to alert me to a change in the amount of co in the cabin that I went looking for and found a cracked exhaust riser.
 
Now compare the CO readings on a Sensorcon or Forensics CO monitor. The CO detector on my Sentry was consistently reading 85-100 ppm, where my Forensics CO monitor regularly reads 0, or occasionally 10-15 ppm in a turn.

The only plus the full size Sentry has over the Sentry mini is the rechargeable internal battery. The CO alarm and the faux-ADHARS are worthless.
It's just a bonus... I didn't buy it for the ADHARS or the CO, just bonuses I guess? Or not?! Works well for what it was intended - ADSB-in and some weather.

I like the sound of the Coexperts @iflyatiger, I'll have to look into that.
 
Not being snarky here, but is this really a danger in the average leaky 172/PA28? With the lack of proper seal on the doors I'd think there's enough fresh air circulation to stave off enough CO concentration to be an issue? Now I guess if you're blowing the heat in it could be an issue.
 
Not being snarky here, but is this really a danger in the average leaky 172/PA28? With the lack of proper seal on the doors I'd think there's enough fresh air circulation to stave off enough CO concentration to be an issue? Now I guess if you're blowing the heat in it could be an issue.
It is a danger. In my incredibly leaky C150, I get 15 ppm on a climb without any actual CO leak, but just exhaust coming in the bottom of my door seal. I can imagine in the winter with the vents closed and a real leak coming in the cabin heat that it could go above 100 ppm very easily.
 
Not being snarky here, but is this really a danger in the average leaky 172/PA28? With the lack of proper seal on the doors I'd think there's enough fresh air circulation to stave off enough CO concentration to be an issue? Now I guess if you're blowing the heat in it could be an issue.

Also not to be snarky, but ummm... yes? I have always assumed it is a very serious issue for all aircraft, but tbh I’ve never considered the “leakiness” of your average spam can?

Either way, I do use our heater all winter long. It gets coooold where I live, especially at 10k’. I have heard of pilots that refuse to use their heater, though, for this reason. Curious what ya’ll’s thoughts are on heater usage?
 
Also, thanks for the recommendations. Just ordered the sealed battery CO Experts model. $200 and checks all my boxes. Hopefully I won’t need it and if I do, it will keep me from dying (I have always felt like morbid humor is worth something in aviation. My wife and I like to play the game, especially when flying in the mountains, “would you rather crash into the forest or should we just lawn-dart it into the waterfall?”).
 
Also not to be snarky, but ummm... yes? I have always assumed it is a very serious issue for all aircraft, but tbh I’ve never considered the “leakiness” of your average spam can?

Either way, I do use our heater all winter long. It gets coooold where I live, especially at 10k’. I have heard of pilots that refuse to use their heater, though, for this reason. Curious what ya’ll’s thoughts are on heater usage?
Hell, I use the heater in the summer. It gets cold at 12,000 ft, especially when you're dressed for summer weather. Even got some ice this July. All the more reason to have a CO detector.

One of our club planes had a cracked muffler and set off the CO detector in the middle of summer with the heater off. The detector in that particular plane was a household model that doesn't alarm until 50ppm. Might have been a bad end without it. The heat valve in our spam cans is not exactly tight, and if a leaky muffler is flooding the engine bay with CO, it doesn't even have to come through the heater system. It can seep in all those little leaks you mentioned @Todd82

Would I fly without a CO detector? Sure. But I'd acknowledge the risk, and at the first sign of a headache or sleepiness I'd be getting on the ground. No reason not to have one as cheap as they are these days.
 
Not being snarky here, but is this really a danger in the average leaky 172/PA28? With the lack of proper seal on the doors I'd think there's enough fresh air circulation to stave off enough CO concentration to be an issue? Now I guess if you're blowing the heat in it could be an issue.

I don't know about you guys but I take every precaution to make my PA28 as NOT leaky as possible. I'm on my third door seal since I've owned the plane. The first one was there when I bought it and was old, brittle and broken. The second was purchased from a company who advertised it worked but was for "light" use. I won't mention the name because someone got all butt hurt that I complained about it on this forum. I guess it all boiled down to the definition of "light." Anyway, that one lasted a month before it started to crumble. I'm now on my third door seal which has lasted three years without issue or leakage of any kind. I make sure to plug up any holes in the firewall or gaps where cables, wires, or pressure lines penetrate and I inspect the heat shroud and muffler which it surrounds very carefully for leaks or cracking. Having said that, exhaust systems with slip joints will leak simply because they are designed to move, making an airtight joint impossible but this is reduced significantly when the engine heats up. I will also stipulate that you are going to get some carbon monoxide in the cabin through exhaust gasses entering through fresh air vents because of the attitude of flight or on the ground but at altitude and in cruise, aircraft shouldn't be leaking carbon monoxide into the cabin. Having said all that, I have a Guardian Avionics 452 mounted in my PA28. I didn't mention it because it is outside the price range of the OP's post.

The airplanes aren't designed to leak and I think its crazy for owners to accept that they just do and not do anything about it.
 
The airplanes aren't designed to leak and I think its crazy for owners to accept that they just do and not do anything about it.
But I love having my lower left leg freezing while the rest of me stays warm......oh, you mean I could replace the door seal? If you volunteer to come over and do it for me in your free time, I will not stop you.
 
In my view, the minimum alarm point of 25ppm is too high for it to be useful for this application.

The second alarm point is at 100ppm, which is silly high for a cockpit.

* Orest
 
In my view, the minimum alarm point of 25ppm is too high for it to be useful for this application.

The second alarm point is at 100ppm, which is silly high for a cockpit.

* Orest


I believe the alarm points are programmable, though.

(Edit). Well, maybe not. I can’t find it in the description now.
 
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I’m considering this one:
https://www.mypilotstore.com/MyPilo...DiytRRrOV-lEFceudVTENwyqb0yfpb9RoCMfAQAvD_BwE

Things I like
1) Can be left on. Battery good for 2 years and replaceable.
2) Sensor is rated for 10 years.
3) Multiple alert levels, programmable.
4) Visor clip for mounting.

Opinions?

Get one with low alarm levels and short dwell times. The Forensics CO detector will alarm at 9 and 25 ppm with a dwell time of 60 seconds at 9 ppm. That's rapid advance notice of an impending problem if it persists.
 
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