CO monitor goes off

[Viktor Eysselein]

For any Hunter owner with installed CO monitors:

When we use the oven on our Hunter 45CC the CO monitors go off - any idea what to do. It is tough to open all hatches in the winter time. Should we run the hood fan at the same time?

Thanks,

Viktor

 

[Johnb]

Please take this very seriously.

For a while some CO monitors were made over sensitive and the slightest whiff (during lighting possibly) could set them off. They can also be triggered by propane (unburned).

Would this happen if you started the oven up with the boat well ventilated and then closed up once it was hot? Do you think you are getting enough fresh air to run any gas appliance with the boat closed up?

You use monitor(s) in the plural so does that mean you actually have two independant units, and they both alarm? If not I would get a second monitor for comparision and see what happens.

If that also gets set off look for a root cause like incorrect burning in the oven. If nothing happens I would get (borrow) a third one to make sure - you are protecting life here!

I would never disable the CO detector(s). We had an exhaust elbow start leaking and it was the CO alarm that was the first indication. If someone had been sleeping down below we could have had a bad outcome.

 

[Benny]

Flase alarms

There are a few other gases besides CO that trip these monitors. The benefits outweigh the faults.

 

[Jeff20919]

We also have a Hunter 45 CC, 2006, on our boat there are two CO monitors, one in the aft cabin, and one in the forward V berth area. Are both of these monitors going off when the oven is in use?

Jeff

 

[Viktor Eysselein]

Dear Jeff:

We have three CO monotors: one in the bow cabin, one in the main cabin and one in the stern cabin. All monitors go off when the stove is on and the fan above the stove is not turned on!

Thanks,

Viktor

 

[Jeff20919]

Viktor,

Where in the main cabin is your CO monitor located?

Jeff

 

[Rich Stidger]

Viktor,

I don't have the same boat model as you, so my question is- Do all three of the CO alarms go off at the same time or do they alarm at different times? My thinking is that if they all go off at once, they are probably connected together to provide that feature. If that is the case, it would be helpful to know which of the three is causing the alarm.

If all three alarm at slightly different times, then that suggests that the CO is present throughout the boat.

Regardless, I would get a second CO detector with a display that shows the ppm of CO present. I would conduct tests with the second CO detector in each of the three locations. It might be that one of the detectors is defective, but you must be certain of the true cause of these alarms. As Johnb posted earlier, this is a serious condition and lives can be lost if mistakes are made.

 

[Viktor Eysselein]

The CO monitor in the main cabin is located at the port side in front of the nav station high up.

 

[Viktor Eysselein]

Dear Rich:

All three monitors go off at different times after the oven is started. The monitor in the main cabin goes off first, then the others.

Thanks,

Viktor

 

[Johnb]

Some Basics

What happens when propane, (C3H8) burns is the propane molecule breaks up into carbon (the 3 C's) and hydrogen (the 8 H's) and the carbon combines with oxygen in the air to form (hopefully) CO2 (carbon dioxide) and the hydrogen combines with oxygen to form H2O (water).

If the oven combustion area is starved of oxygen the there may not be enough for all the carbon to burn completely to CO2, and the result could be unburned carbon (soot) or carbon monoxide, CO. There is a wealth of information on the internet about carbon monoxide but the important thing to know is that it does not just suffocate you. It combines with the haemoglobin in your blood that should be carrying oxygen, but unlike oxygen it never lets go, so it is cumulative and poisonous.

Based on what you report it may be your oven is short of air, maybe a vent blocked or something.