Home › Top 4 Heating and Cooling Services in O'Fallon, Missouri Find best Heating and Cooling Services in O'Fallon, Missouri, with all necessary contact information, including addresses, phone numbers, working hours, map locations, and website links. Craigco Heating and Cooling Company LLC US, O'Fallon, MO 6336615 Drury Ln KirbnJays Heating & Cooling US, O'Fallon, MO 63366674 Whispering Willow Dr Sierra Mechanical US, O'Fallon, MO 63366212 Crafton Dr Stay Cool Climate Control US, O'Fallon, MO 63366407 Sonderen St