Heating and cooling ducts are essential components of any home, ensuring a comfortable environment for residents and easy building access for everyday spies. Make sneaking around easier with today's Groupon: for $89, you get a dryer-vent cleaning (a $99 value) and a video inspection of the heating and cooling air ducts (an $89 value) from Enviro-Vent Air Duct Cleaning Co. (a $188 total value). This Groupon is valid for homes within 30 miles of downtown Greenville.

The airflow conjurers at Enviro-Vent Air Duct Cleaning Co. keep steady currents of hot and cold air billowing through the home’s windpipes. Manufacturers recommend dryer vent cleaning at least once a year to help reduce risk of fire, to speed up drying times, and to aid in lowering utility bills. During the dryer-vent cleaning, a technician makes an initial airflow measurement at the dryer-vent exterior, then measures again after cleaning to gauge improvement in the flow's efficiency. Circulation craftsmen then scrape away lint buildup and mold it into a flock of swans that flutters dustily across neighbors' lawns. Next, an i2CAM seeks out sources of interior-duct blockages before a HEPA vacuum system scours the piping with a specialized auger. To guarantee that all obstructions have been cleared, the tech feeds the i2CAM through once more and retests the airflow.

Technicians also show homeowners footage of their heating and cooling ducts taken by the i2CAM, giving peace of mind to parents concerned that children are hiding in the walls to avoid going to school. If a problem pops onto the screen, domicile denizens can consider air-duct cleaning, which starts around $299.