These photos are some common issues that has happened in numerous residential and commercial jobs. You never know what is right under your nose.
Dryer vent lint build up is a common and serious hazard in the( U.S.) Don't believe us just do some research at www.fema.gov (Residential and Commercial dryer lines should be cleaned at least once a year.)
Outside AC Condensers need to be clear of all dirt and debris in order to be efficient on a day to day. (Clean your condenser units at least once a year ; usually just before spring.)
Your furnace or air handler will more than commonly vacuum in particulates and exhaust them into your home or businesses air space. (Example: Dust, Dirt, Mold, and Vapors) are all common problems we deal with during our cleaning of your HVAC system.
Mold Spores can feed off any dirty surface that it can stick to. This example (photo top right) is a duct system with mold growing in the interior of a duct system with fiberglass duct board.
MOLD RULES: Temperature (AC-Heat) + Moisture (Humidity) + Food Source (Dirt) = GROWTH!