Johnstone Supply

Johnstone Supply has served the Marietta HVAC industry since 1983 as a contractor-only parts warehouse, earning a 4.3-star rating across 43 verified reviews. Located at 2350 Auburn Valley Drive, this distributor supplies licensed HVAC technicians with furnaces, coils, mini-split systems, and field-installed accessories. The company ships equipment to metro Atlanta shops and surrounding Cobb County neighborhoods including Smyrna, Kennesaw, and Woodstock. Customers describe the operation as "the go-to parts warehouse" for professional installers seeking hard-to-find components for aging systems.

What distinguishes Johnstone Supply from general supply houses is its inventory depth on legacy systems. One reviewer noted the team sourced a replacement part for a 10-year-old Amana furnace at reasonable cost when other channels came up empty. The catalog includes residential unitary equipment, variable-capacity systems, multi-zone configurations, and commercial single-packaged units. Extended warranty programs accompany select coils and air handlers. The facility maintains Express Locker Pickup for contractors who order online and require same-day will-call, eliminating time spent inside the showroom.

Customer stories threading through reviews name two technicians consistently: Bob and Chris. Multiple reviewers credit Bob with same-day holiday weekend arrival during sweltering July heat, diagnosing a no-cool call when the homeowner could not reach their own contractor. Another described Chris locating a specific evaporator coil for a 10-year-old system that two other suppliers flagged as obsolete. These scenarios illustrate the practical value a parts distributor provides to homeowners who depend on a working relationship between their installer and a well-stocked supplier.