[Eric Parks]

Eric Parks on February 10, 2026 at 7:55 pm #25716

I recently bought a CO detector that is a new model. Radiant Technology has the RI-2025-10-COPOCKET for about $80. It is a rechargable unit and they say it should last about 6 month on a charge. I just got it so don’t know about that. Unit is fairly small and you can carry it on your person or just have it in the cabin. Maybe velcro it somewhere. The point here is that it’s not part of the plane and so doesn’t require any certification or STC. It has an LCD readout for the CO ppm but the case will flash red and buzz if it reaches a dangerous level. Also gives temperature and relative humidity. 

https://www.radiantinstruments.com/product-page/co-pocket-carbon-monoxide-detector

 
Pen gives an idea of the size

 
Case is translucent white and will flash red and the unit will buzz if it gives a warning

 
Readout is LCD but you can barely see the temperature and humidity on the screen
 
Attachments:
CO1.jpeg
CO2.jpeg
CO3.jpeg

[Kent Shaw]

Kent Shaw on December 8, 2020 at 4:00 pm #20368

I did not take pictures but I have seen pictures that other pilots made that may help. It was a fairly easy project to do. The biggest problem that a couple of pilots reported seems to be damage to heads of the 2 very small screws that hold the valve assembly on when removing the screws. I had no problems with mine. It looks like #2 machine screws but I did not measure them. I used one of the very small jeweler’s screwdrivers and that worked fine. One of the small gunsmith screwdrivers should work as well. Just make sure that your screwdriver is making good contact before you start turning it. You can put the two plates together with aluminum rivets like they were originally made but the #4 machine screws should make future replacement easier.

[STEVE]

STEVE on December 8, 2020 at 7:46 am #20367

Hi Kent;
Did you happen to take pictures during your refurb project? If so, please send them to me so I can pass the details of this repair on to other owners.
Thanks
Steve

[Kent Shaw]

Kent Shaw on December 6, 2020 at 8:03 am #20364

If you feel air from any of your floor vents, then you may need to replace the seals. No one sells new seals so you need to fabricate your own. I got some 1/8″ dense foam rubber off Ebay, removed the vent flappers with a small jeweler’s screwdriver, drilled out the the two aluminum rivets holding the two metal plates together, replaced the foam rubber, used two #4 pan-head machine screw with a #4 washer and a lock nut to reassemble. I used scissors to trim the foam leaving about 1/8 ” of foam sticking out all around..

[George Henning]

George Henning on November 5, 2020 at 5:20 pm #20305

Hi All,
As a new-to-me Seneca owner I was briefed on the importance of proper maintenance and operation of the onboard Janitrol heater.
On the III it’s in the aft fuselage and the ducting runs along the floor forward.
A CO Detector was recommended and I decided on the Otis Detector offered by Sporty’s.
My heater has worked great, the controls are straight forward and located on the aft center console.
The POH gives good guidance.
The Otis Detector is a nice, small unit, runs about $160, has a visual, vibrate and aural warning. The unit is portable and I’ve attached it on a forward map pocket, in full view. The unit battery is good for 2 years and the company would like you to return it for recalibration when time to change the battery.
The highest reading I’ve seen so far is 5PPM, the alarm comes on at 35 PPM.
I agree, go get one, cheap insurance!
Works Good Lasts a Long Time!
George
CLE

Attachments:

• F2B4E58E-2030-4DE7-9D93-348618EFBE4E.png

[STEVEN STOCKMEIER]

STEVEN STOCKMEIER on November 5, 2020 at 1:45 pm #20303

Good call! Just bought it from Amazon. Update on my Forensics CO Detector. The picture looks like it has a blue backlighting in the indicator. It DOES NOT. Almost impossible to view without a flashlight.

Attachments:

• image_2020-12-28.jpg

[Kent Dellenbusch]

Kent Dellenbusch on April 28, 2020 at 9:29 am #19890

For certified installed units, our supporter Guardian Avionics has this one. https://www.guardianavionics.com/guardian-aero-451-101-panel-co-detector-certified-norsee

Attachments:

• co2b.png

[STEVE]

STEVE on April 28, 2020 at 8:42 am #19888

Hi David;
I spent a lot of time trying to determine why there were high levels of CO in the cabin of a turbocharged Cessna 182RG. We would block off openings and fly. Eventually this cheap (cost of tape and avgas) troubleshooting technique revealed that the CO was coming into the cabin through the air conditioning evaporator screen (the airplane had been built as a demo airplane so had all the bells and whistles) on the pilot’s side of the airplane in the tail cone.
The exhaust down pipe terminated on the same side. Theories abounded. Did the CO wrap around the fuselage before entering the vent, or did it just flow aft.
There are two small projecting scoops on the left and right side of the Cessna 180 and 185 tail cone. I’ve been told that Cessna installed those to pressurize the tail cone to prevent exhaust/CO from entering.
This insidious danger isn’t talked about too much, but it’s real so any discovery and mitigation of it is time and money well spent.
A good sensitive and loud detector is a great first step.

[David]

David on April 23, 2020 at 4:10 pm #19878

Thanks for the information Steve,
Whereas I’m not too worried about the levels or exposure times, it’s good to know where it’s coming from. I was looking for some confirmation if the left air inlet sounds like a reasonable explanation.
Dave

[STEVE]

STEVE on April 22, 2020 at 9:55 am #19871

Thanks for this report.
I urge everyone to own and carry a CO detector when flying. As you illustrated, the heater which is the main source of CO in our airplane cabins does not have to be on for CO to enter the cabin.
Short exposure to the levels you’re experiencing are generally not hazardous. Here’s a report with some guidance:
The health effects of CO depend on the CO concentration and length of exposure, as well as each individual’s health condition. CO concentration is measured in parts per million (ppm). Most people will not experience any symptoms from prolonged exposure to CO levels of approximately 1 to 70 ppm but some heart patients might experience an increase in chest pain. As CO levels increase and remain above 70 ppm, symptoms become more noticeable and can include headache, fatigue and nausea. At sustained CO concentrations above 150 to 200 ppm, disorientation, unconsciousness, and death are possible.
I do not recommend using the little stick on detectors that change colors with exposure to CO. Good detectors are available with warning sounds for around $100.
I use this one: https://www.amazon.com/Aircraft-Monoxide-Detector-FORENSICS-low-level/dp/B076S6KBP2.
Best,
Steve