Home>Discussions>INSULATION & HVAC>Ventilation of new, high efficiency furnace to outside, through wall
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ruth white
Ventilation of new, high efficiency furnace to outside, through wall

I have recently (fewer than 30 days ago) had a new ac/furnace installed (Amana, model GMH9590HC). I turned on the heat yesterday, for the first time, and noticed that the furnace had veen vented through the wall. There was white "smoke" wafting, as from a dryer vent, except this "smoke" had an odor, drifted back into the house, made me dizzy, and gave me a headache. I turned the furnace off, opened the windows, and the symptoms disappeared.

I had been under the assumption that a furnace should be vented through the roof, but after consulting your message board, learned that high efficiency furnaces can safely be vented through the wall, using PVC pipe, which this furnace was.

I can live with the wall vent, although I do not like it, aesthetically. But should it emit white fumes? Should the fumes have an odor? And should it cause headaches and dizziness? This, of course, was not an issue with the old, 40-year-old furnace. The installer is a reputable, local business, with whon I have traded for thirty years. Your thoughts?

I am concerned regarding safety; my five-year-old grandson lives with me.

Thanks in advance for any information you may provide.

Re: Ventilation of new, high efficiency furnace to outside, through wall

The white smoke is water vapor like a dryer vent, mixed with the products of combustion including carbon monoxide. It will have an odor.
Since you have a reputable installer, he should be able to correct the problem. Maybe an extension or relocating the through wall flue. I'm surprised the smell got into the house if the windows were closed. Maybe their is a problem with the flue in the house. Getting a CO detector would be a good idea in any event.
One more thing, the smell may have been the smell of the new furnace burning in. The more I think about it, the more I suspect that. I would still call the installer to voice your concern.


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