| Business | Phone |
| A Precision Air Heating & Cool 853 Mid Point Dr, O Fallon 63366 | (636) 240-9995 |
| B & B Heating Cooling & Const 1339 Sunview Dr, O Fallon 63366 | (636) 272-7384 |
| Brown's Heating & Cooling 2788 Highway Y, O Fallon 63366 | (636) 272-2041 |
| Merkel Mechanical Svc 887 Mid Point Dr, O Fallon 63366 | (636) 978-7599 |
| Ken Mills Heating & Cooling 2123 Chickadee Ct, O Fallon 63366 | (636) 949-8010 |
| Hoff Heating & Air Cond Inc 1520 Kemmar Ct, O Fallon 63366 | (636) 240-4633 |