BobRip
Elite Member
NewToy said:How do those ventless units work? It seems like you'd have a CO buildup with those things. Where do the by products of combustion go? The wife has been pestering me to install one for the visual effect. We have a geo-system with the ground loop for heat, it does a fine job.
John
Non-expert explanation follows. The theory is that the combustion process is so complete that the only combustion products are CO2 and water. No CO is created. On some units (maybe all) there is an oxygen depletion sensor that shuts the unit down if there is not enough makeup air getting into the room and oxygen gets low. Being a skeptic I have trouble believing in such perfection, on the other hand this system is 100% energy efficient and that's great. Also I assume that it is UL or otherwise listed so it's probably OK. They are very picky about their approvals. They have been on the market several years so they are again probably OK. Do a little web surfing and see if there are issues.