You will have to test to know.
You can purchase Mold test kits from our site ( http://www.startremodeling.com/solutions/store/mold_test_kits.html )or you can look at your local home depot or lowes.
They run about 10 bucks and will help you to pinpoint the problem.
I would start with testing the ac exhaust vents.
Here's a brochure to explain the process.
http://www.startremodeling.com/toxic_black_mold_test_kit_brochure.htm
Good Luck!
Let me know if you have more questions.
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Jimmy McDonald
http://www.StartRemodeling.com
Jimmy@StartRemodeling.com
http://www.ToxicMoldUSA.com
McMoldMan@ToxicMoldUSA.com
Jimmy McDonald ( RemodelingGuy) specifically assumes no legal liability or responsibility for the accuracy, completeness or usefulness of any information or process disclosed. The above further expressly advises that any use of or reliance upon the information and or opinion disclosed is at your risk .
_________________________
Jimmy McDonald
http://www.StartRemodeling.comJimmy@StartRemodeling.com
http://www.ToxicMoldUSA.comMcMoldMan@ToxicMoldUSA.com
Jimmy McDonald ( RemodelingGuy) specifically assumes no legal liability or responsibility for the accuracy, completeness or usefulness of any information or process disclosed. The above further expressly advises that any use of or reliance upon the information and or opinion disclosed is at your risk .