CO Detector Keeps Going Off

[Natesms]

I've got a Chris Craft 33 Crowne Express Cruiser, and I replaced the CO detector in the cabin at the very beginning of the season.

Throughout the season it has gone off somewhat randomly. We can be cruising down the lake without the generator at 30 mph and it'll go off. Other days I can run all day, generator on with no problems. I've even been on the hook with genni running for 10 hours and it never went off.

The last couple of months it started going off after we were back in the dock with everything shut down (15 - 20 minutes after getting back and everything off).

Anyone have any suggestions on what could be going on? Could the thing be overactive? I've checked for exhaust leaks off the motors and generator and nothing sounded odd. Blower is strong. I have Volvo Duoprop drives with under water exhaust.

I obviously don't risk anything, if it goes off, I throw open all the hatches and pull anyone in the cabin out (normally we are cruising down the lake when it's gone off, no enclosure upstairs so fresh air is no issue). If we are at the dock everyone off the boat. Sometimes hitting the reset button will clear it right away, other times it'll go off again.

 

[agallant80]

Re: CO Detector Keeps Going Off

Its not unheard of for a CO detector to go off with no reason. With that said you need to find out why its going off. This is something that can kill you. Even going off at the dock with everything shut down does not mean you are safe, CO from another boat could be blowing in to your boat. I would start with adding a 2nd new detector. Get one that has a digital read out of the PPM count of CO. Inspect all of your exhaust connections, you could even get a hand held CO detector and use it to check the engines and generator when running for leaking exhaust connections.

 

[bajaunderground]

Re: CO Detector Keeps Going Off

Get a second one and see if it reacts the same? CO detectors can malfunction due to dust, steam, condensation, insects. My $.02

~bRett

 

[Natesms]

Re: CO Detector Keeps Going Off

I'm guessing they have battery powered ones at lowes with the readout?

 

[agallant80]

Re: CO Detector Keeps Going Off

Yes. I bought one of those and keep it in the sleeping area of my boat. I have three detectors on my boat. The one marine hard wired one and two from Lowes one with a readout.

 

[Fireman431]

Re: CO Detector Keeps Going Off

Even tho you are running 30 MPH, depending on how the wind is blowing or if the "station wagon" effect happens, it'll go off. CO detector should be hard wired with a battery back up. The likely culprit would be a minor leak in the engine exhaust and you're getting exhaust into the cabin. I wouldn't be so quick to call it a failed detector. They are pretty sensitive, tho.

 

[rbh]

Re: CO Detector Keeps Going Off

I have seen how easy it was to set the detectors off just by breathing on them, so if your on the water and the cuddy is an enclosed area, next to no ventilation with a few people just breathing, that can do it.

 

[The Great Escape II]

Re: CO Detector Keeps Going Off

They also turn on if you have a low battery.

 

[Natesms]

Re: CO Detector Keeps Going Off

I hunted for a detector with a readout at lowes last night and they didn't have anything in stock. Going to try Home Depot and will hopefully get a better idea of what is going on this weekend.

My main concern is a small exhaust leak might exist somewhere in the engine compartment. I also know that we get the "station wagon" affect pretty good on this boat. I plan to put the canvas up this weekend so I need to get that 2nd detector I can keep up in the cockpit.

I appreciate all the input.

 

[MarkSee]

Re: CO Detector Keeps Going Off

They also turn on if you have a low battery.

^^^^^^
I would check this also for a couple of reasons.

1-I just decided to replace mine as it was going off too even without the engine running realizing it was low battery input; both batteries needed some charging. As far as I knew this was the original detector so I just decided to replace it anyway.
2-you indicated, by what I understand from your post, whenever the generator was on and running, supply 12v power also I'm guessing, it never sounded. The generator may have been provided the slightly extra power the detector needed.

Guess maybe checking the connections are clean, good ground, etc. would not hurt.

Mark

 

[agallant80]

Re: CO Detector Keeps Going Off

I hunted for a detector with a readout at lowes last night and they didn't have anything in stock. Going to try Home Depot and will hopefully get a better idea of what is going on this weekend.

My main concern is a small exhaust leak might exist somewhere in the engine compartment. I also know that we get the "station wagon" affect pretty good on this boat. I plan to put the canvas up this weekend so I need to get that 2nd detector I can keep up in the cockpit.


I appreciate all the input.

That is what I do. I have two mounted down below and one that I can take in to the cockpit when we have things running with the canvas up.

 

[Natesms]

Re: CO Detector Keeps Going Off

I'll check the low battery / bad voltage to the connection. I have brand new batteries, however I noticed mid way through the summer that the 12 volt power outlet right next to the detector wouldn't property power my small 250 watt inverter even when the engines were running. Could definitely be something there.

 

[Natesms]

Re: CO Detector Keeps Going Off

Well I completely forgot the volt meter so I wasn't able to check that.

I did set a new battery powered detector close to the wired one. The wired one went off while driving around and the battery powered one did not. I'll have to check the voltage next trip down there. It kept going off in the dock for almost an hour after I shut eveything down so I just unhooked it and left the battery powered one in its place.