Since 1974, Specific Systems, LLC. has held strong to a commitment of reliability, service and design excellence in special purpose environmental air conditioning, heating, ventilating and pressurization systems. This has been accomplished through proven engineering and design principles combined with a dedication to continued improvements in our standard modular products.

With this strong engineering focus, Specific Systems leads the industry in modular environmental control system technology.

Industry Proven Reliability

Many environmental control units (ECUs) used in special industrial applications are simply modified versions of commercial-duty units. The very nature of a modified commercial unit requires compromises in features, quality control, and supportability. Fully custom one-of-a-kind units are costly, can take a very extended amount of lead time to design and fabricate, and carry the associated risks with first run designs. Specific Systems solves these problems with our modular InPac series product line engineered specifically for heavy-duty industrial use in petrochemical, process, and power industries. The Specific Systems InPac Series is the most extensive line of industrial HVAC units specifically designed for these applications.

Ranging from 2 to 50 tons, Specific Systems units are designed to provide safe and effective environmental control under the most difficult conditions. For more than 45 years, Specific Systems has been manufacturing ECUs that perform reliably in the most challenging industrial applications, including hazardous, explosive areas. While the standard InPac modular design is based on a wall-mount configuration, pad, roof, and split system designs are available using the same standard proven modular designs and components.

Record of Innovation

Specific Systems pioneered the use of redundant refrigeration circuits as a standard design, and set an industry standard for custom industrial wall-mounted units with its first InPac system.

That tradition of innovation continues today in each of Specific Systems product lines. Our adoption of ozone-friendly R-410A as our standard refrigerant and use of high quality materials such as 16-gauge hot-dipped galvanized steel, stainless steel, copper, etc, as well as industrial wiring methods improve the serviceability and service life of the units. Modern standard cabinet design improvements have refined the fit, finish, and service accessibility of the ECUs.

Customization is Standard

With our history of defining the benchmark for industrial packaged HVAC and pressurization along with the skill of our experienced engineers, we are able to provide a standardized solution with many optional features to fit your individual application. Using our modular design, a standard vertical wallmount unit design can be easily reconfigured to a fully-explosion proof rooftop, pad-mount, or split configuration, incorporating optional features such as chemical filtration, steam or electric heat, gas alarms, and fresh air stacks. Modular options like these allow much shorter lead times than are available with fully custom units.

Redundant dual refrigeration circuits are standard on all InPac units 3 tons and larger, and are an extremely important asset in critical applications. The inherent redundancy of two complete refrigeration systems allows for a 50% cooling system backup in the event of a single circuit failure and extends the life of the compressors and other components by alternating cycles between the circuits. 100% complete redundancy is also available with backup evaporator blowers, fans, and isolated dual controls. InPac units can also serve to purge and pressurize the conditioned area when necessary, and when required by NFPA 496 area reclassification.

The standard InPac design packages all options in a single, standard, fixed-width enclosure (i.e. frame size) offering ease of maintenance seldom found in custom industrial ECUs. InPac wall-mount units can normally be fully serviced from inside the conditioned area, with easy access to the systems dual refrigeration circuits and controls. This through-the-wall maintenance accessibility is very desirable when the units are installed onto a pier-mounted building.

Six reasons you can depend on us
and our capacity to perform.


Specific Systems is committed to building the best environmental control systems in the industry. Our engineering expertise and experience gained through 40 years in business enables us to design and build systems that will perform reliably in virtually any application. You can always depend on Specific Systems‘ equipment for durability, reliability, and performance.

Engineering Excellence

At Specific Systems, our team of engineers stands ready to work with you in evaluating and designing an environmental control system suited to your specific application. We assign an engineer to oversee your project and serve as liaison between you and our specialists.

Customized HVAC engineering capabilities are something you can always depend on at Specific Systems.

Minimal Down Time

With Specific Systems’ standard modular environmental control units, you can significantly reduce costly down time. Our engineers have designed a modular product line that offers dual redundancy, fast, easy, on-site or remote repair, and simplified parts replacement. You can depend on Specific Systems modular concept to save substantial time and money.


Specific Systems is committed to meeting your needs. Our standard modular product line can be configured to horizontal, vertical, slimline or split system arrangements using the same standard modular components in each configuration. The most demanding custom needs can usually be accomodated for your particular application. Whatever your requirements, you can depend on Specific Systems to provide the best system for your unique needs.


Specific Systems takes pride in manufacturing top quality environmental control equipment. From the initial stages of engineering, throughout production, and into the final stages of assembly, our employees maintain a well-documented high standard of quality control.

We have been certified by Intertek to meet each current ISO 9001 standard since 2011.

At Specific Systems, you can depend on our quality every step of the way.


Our goal is to work with you in a timely, professional manner to get the results you want. We’ll always be available to answer your questions and provide you with the necessary technical information. Our technicians will monitor the performance of your system following installation to ensure maximum operating performance. You can depend on Specific Systems service before, during and after the installation of your system.