Ceiling damage Ductwork Condensation/Water (not in attic)...
Originally Posted by Fairview
I respectfully disagree. Increasing the air temperature 4° increases duct temperature via return air therefore decreasing the chances of reaching dew point.
The space between the first floor ceiling and second floor's floor. Is probably at 78°F and 55% RH, or higher. If the return air temp is 74, and the temp difference across the coil is 20 degrees. making the supply duct 54°F. It will still sweat, as the dew point or the conditions I posted is 60.5°F. Even if the temp difference between supply and return ws only 14 degrees, the supply duct would be 60, so just under dew point.
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