Cummings J.B.
Bibliographic info:
ASHRAE IAQ Applications, Vol. 5, n° 4, Fall 2004, pp 4-5, 1 Ref.

There are two ways for unbalanced return air to produce moisture and mold problems during hot and humid weather : - the increased entry of outdoor air that substantially increases indoor relative humidity. - a negative pressure can draw moist air into wall cavities causing a moist interstitial microclimate, if indoor humidity is relatively low in the conditioned space.To prevent the creation of moisture and mold problems, properly sized return ducts should be provided.