Help, Class C Carbon Monoxide issue

[jsweeney14]

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I need help, I am at a loss. I have a class c motorhome. My co alarm kept going off, so I bought a new one, new one shows levels from 30-150ppm. I am hooked to shore power and I have no fuel burning (motor is off, propane tank is closed) Where could the CO be coming from??

When I pull outside air from the bathroom vent and push air out the stove fan, co levels fall to 0 within minutes.

 

[DonTom]

Is the alarm mounted close to your L-A house batteries? Check the venting of the house batteries. That (and countless other things ) can cause such false alarms. They can smell things we can't.

-Don- Auburn, CA

 

[jsweeney14]

Thanks for the reply Don. In my hunt for an explanation overcharging of the house batteries has been the only plausible answer.

 

[Gary RV_Wizard]

Is the alarm mounted close to your L-A house batteries? Check the venting of the house batteries. That (and countless other things ) can cause such false alarms. They can smell things we can't.

That advice would apply to LP gas detectors, but not CO detectors. There is no CO emitted from batteries or aerosol sprays or whatever. And CO is completely odorless.

CO is formed from incomplete oxidation (usually in combustion). The normal product of combustion is CO2, but CO forms if there is insufficient oxygen available.

 

[Gary RV_Wizard]

Is there any appliance that has a pilot light? The pilot could be burning even though the appliance if "Off", e.g. an oven.

 

[jsweeney14]

That advice would apply to LP gas detectors, but not CO detectors. There is no CO emitted from batteries or aerosol sprays or whatever. And CO is completely odorless.

CO is formed from incomplete oxidation (usually in combustion). The normal product of combustion is CO2, but CO forms if there is insufficient oxygen available.

So apparently overcharging lead cell batteries can release hydrogen gas which will then set off a co alarm. My house batteries so sign of overcharging, so I assume that is the issue and I probably have a faulty converter.

I do not have any appliances they have a pilot.

Thank for your help.

 

[DonTom]

There is no CO emitted from batteries

I never said L-A batteries emitted CO. But we do not live in a perfect world where things only detect what they are designed to detect.

See here.

• Lead acid battery chargers produce hydrogen gas which sets off CO detectors. Keep this in mind if you are charging your caravan/boat battery at home.

-Don- Auburn, CA

 

[Kirk]

I did a lot of digging and the national fire association states: "The typical CO detector is designed to activate when the unit detects 150 parts per million (ppm) of CO for 30 minutes. That same detector will also activate when exposed to 300 ppm of hydrogen gas for 30 minutes. The amounts of hydrogen gas produced during lead acid battery charging in golf carts far exceed 300 ppm." With RVs also using deep cycle or golf car batteries, the possibility does exist. But the catch is that the effects of CO is cumulative over time so even moderate exposure can do serious harm. You need to be very sure that your problem is not CO.

 

[Gary RV_Wizard]

OK, I stand corrected. Excessive Hydrogen gas can trigger a CO alarm.

 

[DonTom]

OK, I stand corrected.

It's not often any of us get that chance to correct you, so I jump on such an opportunity!

-Don- Auburn, CA

 

[jsweeney14]

For anyone who was curious, after fixing the charging issue, my CO sensor has read 0ppm for 2 days now.

 

[Gary RV_Wizard]

It's not often any of us get that chance to correct you, so I jump on such an opportunity!

Every once in a while I demonstrate that I too am fallible.