Carbon monoxide worries
QBefore purchasing our 2004-built boat in 2015 we had a new Boat Safety Scheme certificate examination done. We know the previous owners of our boat and it has always been properly maintained. Up to now we have had had no concerns about the cooker: no smell or fumes and no sounding of the CO alarm, but last weekend we noticed a quite strong fume smell. We looked at the monitor readings, which were rising up through the 20s to the 30s and up to 47 ppm (no alarm has yet sounded) and turned the hobs off. The CO readings are normally at zero. The window opposite the cooker had been open all the time. All of the hobs seem to have the same odour effect. However, using the oven produced no monitor reading issue and no fume odour.
The cylinder is the same one in use when we took over the boat. It is a great deal lighter and it can’t be long before we need to change to the second cylinder. We suspect the answer is to get the cooker serviced. But can ‘old’ gas in a nearly empty cylinder be a cause of this kind of problem? We also have a gas-fired warm air heating system on the boat, which last autumn worked seemingly well. Should we also have this serviced as a precaution? Is there a Gas Safe accreditation for LPG/ propane appliance servicing for boats?
AThe stenching agent added to bottle gas can occasionally settle out so it becomes more concentrated as the gas gets close to running out, producing a smell when the gas is used – but I have no idea if it produces more CO. As the oven does not do this, I suspect the high CO probably wasn’t from the cooker (but the smell might be); Carbon monoxide doesn’t have any smell.
Check that none of the burners have yellow in the flames and that none of your pans develop soot on the bottom. My guess is that you may have been having CO blown into your boat from someone else’s stove, generator or engine exhaust – more common than people think, especially in marinas and crowded moorings.
Gas Safe engineers need endorsements for bottle gas and marine work. Check the Gas Safe a website.
When well clear of other boats, try the other cylinder: if the problem does not recur, it was probably CO being blown in.