Specifically, why does my forced air gas furnace need a drain hose? Is it pulling that much moisture from the air? It’s just a trickle, but it’s hard for me to fathom that air has any moisture left after going through blowers, vents, burners, etc.
Water vapor is a byproduct of the combustion. It’s not pulling the moisture from the air like an air conditioner does…
BTW make sure that drain hose is free of any clogs or kinks. If it backs up your furnace will shut off.
E.G. Ventless gas fireplaces put out so much moisture into the air that some are required to shut off automatically when the humidity levels in the room/home get too high.
High efficency heaters need a drain. By products of combustion are CO2 and H20. With an older furnace the exhaust temprature is usually way above the due point and there not a problem.
But on a 90%+ furnace the exhaust temperatures are much lower. In fact can require that the vent not be made of sheet metal because of rust.
Given the location of the questioner, it’s highly possible that she doesn’t have a condensing furnace (like you would see in the UK), but rather that she has something like an Aprilaire humidifier and the trickle is the runoff from that. That sort of setup is very, very common in the Midwest - in fact, it’s what I have in my basement right now.
Beat me to it!
Without more information, I’m sure that’s exactly what it is.
I don’t pay attention to my furnace at home, but I can tell you that the one at work (which heats an area about the size of a small house, though it probably runs more then twice as much) does not have an Aprilaire, but does put out plenty water.
Sure, condensing furnaces are around, yours very well may be one. They’re just not very common in the US, IIRC, for home use.
Thanks, everyone!
We have an Aprilaire humidifier but the furnace drained moisture on its own, before the Aprilaire was installed. It’s a Lennox pulse furnace, 80% efficiency rating.
Oh, and something new to me! The repairman was here yesterday, and showed me a filter clogged with iron/rust deposits. :eek: He said it takes years to build up enough of this stuff to affect the furnace’s operation.
The reason I asked was because my husband though maybe the furnace had a “built-in” humidifier.