Hey Ed, Do Furnaces Dry Out the Air?
In this edition of "Hey Ed", Ed discusses if furnaces dry out the air in Manual P.
Hey Ed, do furnace is dry out the air? That’s a good question and as much as it pains me to say it, sort of but not really. When a furnace operates in the wintertime, it heats the air and the relative humidity in that heated air drops. But when the air comes out of the supply vents and mixes with the room air, that relative humidity is still there. But people will say "but Ed it gets dry my house in the wintertime" and it does. Most, if not just about all, forced air systems create an imbalance between inside and outside when they operate. They increase infiltration or exfiltration. So, the reality is your house is either getting slightly pressurized a deep pressurized. Infiltration is increasing and we’re driving that warm moist air from inside outside and replacing it with cold dry air. The net result is, we’re gonna have a lower humidity in the space and that’s the way I see it!
In this edition of “Hey Ed”, Ed discusses if furnaces dry out the air in Manual P.
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Ed Janowiak is the Manager of HVAC Design Education at ACCA.
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Posted In: Hey Ed, Technical Tips