2021 Honda Generator Carbon Monoxide Indicator

[robby]

Only if the sensor was actually covered. Seems like nobody knows for sure where it actually is located. If a CO senor is sealed completely from the outside air, there is no way it can sense anything and trip. I tried this with a portable CO alarm and it read zero the whole time I left it near the exhaust.

If you read the post above mine the idea was to make sure that the pinhole on the CO Minder control panel is not the actual sensor. He covered it to test that theory. We now know for sure that the actual sensor is somewhere else.

 

[robby]

Did you also remove the cover and take a reading of the exhaust?

My car, when well tuned, is down in the 1 ppm CO range according to smog check. These generators, not having O2 sensor controlling mixture, air injection, or catalyst probably do create enough CO to trip the alarm, but would be interesting to check. Propane equipment (Bobcat, floor polisher) is operated indoors, and I think CO only becomes a problem if O2 levels drop. Gasoline & diesel generators are known for carbon monoxide even operating in fresh air, and if their exhaust gets indoors it can be deadly.

The big one your missing is that these generators do not have Catalytic converters, your car does!

 

[OM617YOTA]

I also pulled the entire LED/button assembly out of the panel and zip tied a plastic bag around the whole assembly. No difference.

 

[robby]

I also pulled the entire LED/button assembly out of the panel and zip tied a plastic bag around the whole assembly. No difference.

BTW interesting quote from the 2200iS manual.

"The Oil Alert/Check Indicator also comes ON when the engine is automatically
stopped by the CO-MINDER"

I wonder if they just put the CO shutoff in series or parallel with the oil level low switch?
That would mean just disconnect it from the harness and bridge the wires or just disconnect it, depending on if the oil switch is NC or NO. The oil level SW should still work properly.
Just throwing this out there! Also the sensor must be behind the air intake below the front panel.

I wish I could assist but I have hit into several problems during my PV install and it is eating up all my free time.

 

[OM617YOTA]

That's a heck of an insight. The low oil shutdown light does turn on, I bet you're right. Usually those are NO, then close to ground the coil and shut down the device, so they should be able to be just disconnected, without impacting normal operation. This can be tested.

Even if it can't be isolated from the low oil shut down, in an emergency I'd rather run with no oil shutdown safety than not run at all.

 

[robby]

Even if it can't be isolated from the low oil shut down, in an emergency I'd rather run with no oil shutdown safety than not run at all.

If it works we still need that low oil shut off. It saved my Genny once and I think it's a good thing to have.
Should be simple to keep it while removing the CO. Assuming they are using the same shutdown lines.

 

[OM617YOTA]

Agreed, would much rather have the low oil shut down. Poo happens.

 

[MikeDVB]

I've just been browsing mostly and happened across this thread. Everybody is searching for what to unplug or disable to disable the CO Minder.

Has anybody tried sourcing the part from Honda/a dealer? Would be good to know how much it costs and, perhaps, have a spare on hand but beyond that knowing exactly what it looks like will certianly help you identify the one already on the machine.

I've been considering picking up one of these generators myself. I'll likely plumb the exhaust outside of the enclosure but I would still personally like to be able to disable the CO2 System if needed.

Should have got one last year when I was thinking about it.

 

[stienman]

I had to go through a lot of Honda generator manuals to find one that had the CO Monitor in the manual. Most of the manuals on their website reflect the 2019 versions of their units.

Page 99 of this manual has the wiring diagram:

https://cdn.powerequipment.honda.com/pe/pdf/manuals/00X31Z266210.pdf

The CO Monitor is located near the top center of the diagram, with two connectors - one going to the indicator unit, and one going to the AVR - automatic voltage regulation - unit.

The AVR pretty much controls everything, and the cable between it and the Monitor is a communications cable, with RX and TX lines, so it's likely that there won't be a simple wiring change that will disable the CO monitor. The AVR probably communicates with the monitor and if it doesn't get the right responses won't turn the generator on.

However, you should be able to find the CO monitor following these two cables, and enclose it in an airtight container.

If the CO Minder indicator LED goes directly to the AVR, you may have to enclose the entire AVR unit, or disassemble it, find the CO monitor inside, and cover that.

 

[robby]

I've just been browsing mostly and happened across this thread. Everybody is searching for what to unplug or disable to disable the CO Minder.

Has anybody tried sourcing the part from Honda/a dealer? Would be good to know how much it costs and, perhaps, have a spare on hand but beyond that knowing exactly what it looks like will certianly help you identify the one already on the machine.

I've been considering picking up one of these generators myself. I'll likely plumb the exhaust outside of the enclosure but I would still personally like to be able to disable the CO2 System if needed.

Should have got one last year when I was thinking about it.

I have personally tried also looked at the RV threads which are full of posts about people who have tried to get the part and were told its not in stock yet. There is not even a picture of it on the internet and from what I am hearing Honda has no plans on releasing it just yet as the first units to need one won't be showing up at repair centers until 2028-2030.

 

[crossy]

Looking at that diagram it might be as simple as removing the "Y" (oil) wire from the AVR, this would also retain the low oil engine stop function.

 

[stienman]

Looking at that diagram it might be as simple as removing the "Y" (oil) wire from the AVR, this would also retain the low oil engine stop function.

Huh. I think you're right. The AVR's connection to the engine is only on that one wire. If the AVR is expected to shut down the engine in a high CO situation, it could only do so through that yellow wire.

It's possible the AVR will also drop the field winding or exciter, leaving the output off even though the engine would be left running, so it might not be sufficient, but it would be interesting to cut the yellow wire on the two pin connector on the AVR and see what happens.

 

[robby]

Looking at that diagram it might be as simple as removing the "Y" (oil) wire from the AVR, this would also retain the low oil engine stop function.

Yes I noticed that but it would probably only apply to this model, I have not seen schematics this clear for other models like 2200 and 3000.

 

[crossy]

All these engines are stopped in the same way, by grounding out the "stop" wire on the magneto. So removing the equivalent connection should leave the engine running, of course as @stienman notes the AVR could also kill the excitation.

Otherwise time to get out the communications sniffer on that data link. Could be a market for a "CO sensor emulator". Sadly (?) I don't have one of these generators to experiment on, it would be an interesting project.

 

[Texas-Mark]

I would be concerned that it has a "one wire" sensor that is interrogated every few seconds . I thought I read that it will give a warning at some point before it is about to expire. So it would seem there is some sort of data communication going on. I still think the best bet for now is to find the actual sensor and seal it up.

 

[robby]

I would be concerned that it has a "one wire" sensor that is interrogated every few seconds . I thought I read that it will give a warning at some point before it is about to expire. So it would seem there is some sort of data communication going on. I still think the best bet for now is to find the actual sensor and seal it up.

All of that would probably still work the same, it's possible that you can just cut one wire and the Gen will never shutoff again. You will still get flashing CO lights and all the warnings but it just can't shutdown the generator.

 

[Texas-Mark]

All of that would probably still work the same, it's possible that you can just cut one wire and the Gen will never shutoff again. You will still get flashing CO lights and all the warnings but it just can't shutdown the generator.

Ok, I see what you are saying, the computer would want to shut down, but the actual shutdown wire is cut. That may work, but the computer may also tell it to go to idle mode or some other action that would inhibit normal operation.

 

[OM617YOTA]

Wonder what the control system differences between an inverter and non inverter genny are.

 

[Hedges]

vs.

 

[stienman]

All of that would probably still work the same, it's possible that you can just cut one wire and the Gen will never shutoff again. You will still get flashing CO lights and all the warnings but it just can't shutdown the generator.

Did you try any of these changes, and did anything work?