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Thermo Forma 3940 Refrigerated Environmental Chamber
The Thermo Forma 3940 Refrigerated Environmental Chamber is a large-capacity environmental chamber designed for precise temperature and humidity control across a broad operating range. Unlike traditional laboratory incubators that operate only above ambient temperature, the Thermo 3940 provides reliable refrigeration, heating, and humidity control from 0°C to 60°C, making it an excellent solution for stability testing, pharmaceutical storage studies, environmental simulation, product shelf-life evaluation, and biological research.
With a generous 29 cubic foot chamber, precise microprocessor controls, and excellent temperature uniformity, the Thermo Forma 3940 is widely used by pharmaceutical manufacturers, biotechnology companies, universities, and quality assurance laboratories that require consistent environmental conditions over extended testing periods. Purchasing a refurbished Thermo Forma 3940 from American Instrument Exchange allows laboratories to obtain dependable environmental testing equipment while significantly reducing equipment costs.
Key Features
Large 29 cu. ft. chamber capacity
Temperature range from 0°C to 60°C
Relative humidity control from ambient to 95% RH
Temperature resolution of 0.1°C
Excellent temperature uniformity (±0.3°C)
Microprocessor-controlled temperature and humidity regulation
Directed airflow system for uniform chamber conditions
Solid insulated door for improved environmental stability
Designed for ICH stability and environmental testing applications
90-day warranty from American Instrument Exchange
Designed for Stability Testing and Environmental Simulation
The Thermo Forma 3940 was engineered for laboratories that require highly stable environmental conditions over extended testing periods. Its refrigeration system allows operation both below and above ambient temperature, making the chamber suitable for applications that conventional laboratory incubators cannot accommodate.
Advanced airflow management distributes conditioned air evenly throughout the chamber, minimizing temperature variation between shelves even when the chamber is heavily loaded. The combination of refrigeration, heating, humidity control, and precise electronic controls allows laboratories to confidently perform long-term testing without compromising environmental consistency.
Many laboratories use the Thermo Forma 3940 alongside laboratory refrigerators for sample storage, ultra-low freezers for long-term preservation, CO₂ incubators for cell culture applications, and biosafety cabinets when preparing sterile biological samples.
Common Applications
The Thermo Forma 3940 is frequently used for:
Pharmaceutical stability testing
ICH storage studies
Drug development
Shelf-life testing
Controlled environmental testing
Seed germination studies
Plant research
Entomology research
Biological incubation
Packaging validation
Food and beverage testing
Quality assurance laboratories
Its ability to precisely control both temperature and humidity makes it suitable for a wide range of scientific and industrial applications.
Ideal Laboratory Environments
The Thermo Forma 3940 is commonly found in:
Pharmaceutical manufacturers
Biotechnology laboratories
Contract testing laboratories
Quality control departments
University research facilities
Agricultural research laboratories
Food science laboratories
Environmental testing laboratories
Government research facilities
Its large chamber volume also makes it an excellent choice for laboratories processing high sample volumes or testing oversized products that cannot be accommodated in smaller environmental chambers.
Temperature Uniformity and Recovery Performance
Maintaining consistent environmental conditions throughout the chamber is essential for reliable stability studies. The Thermo Forma 3940 utilizes a directed airflow system that continuously circulates conditioned air throughout the chamber, providing excellent temperature uniformity across all shelf locations.
The refrigeration and heating systems work together to rapidly restore programmed conditions following routine door openings. Fast recovery minimizes disruptions during sample access and helps maintain consistent testing conditions throughout long-duration studies.
Precise electronic controls allow temperatures to be programmed in 0.1°C increments, giving researchers the flexibility to perform a wide variety of environmental testing protocols.
Humidity Control
In addition to temperature regulation, the Thermo Forma 3940 provides active humidity control from ambient conditions up to 95% relative humidity. Laboratories can independently program humidity levels to simulate storage environments required for pharmaceutical stability testing, packaging validation, biological research, and environmental simulation.
The humidity system offers 1% RH readability and helps maintain consistent moisture levels throughout extended testing periods, improving the repeatability and reliability of long-term studies.
Sample Storage Recommendations
The spacious 29 cubic foot chamber accommodates a wide variety of laboratory materials, including pharmaceutical products, stability samples, medical devices, packaged products, research specimens, plant samples, insect colonies, culture media, biological samples, environmental testing materials and more.
The large interior provides ample room for multiple shelves of samples while maintaining uniform environmental conditions throughout the chamber.
Energy Efficiency and Operating Costs
The Thermo Forma 3940 combines insulated cabinet construction with efficient refrigeration and heating systems to minimize energy consumption while maintaining precise environmental control.
The solid insulated door helps reduce temperature fluctuations and refrigeration demand during operation, while intelligent electronic controls minimize unnecessary cycling of heating and cooling components. These design features contribute to dependable long-term operation while helping reduce operating costs.
Key Specifications
Specification
Details
Manufacturer
Thermo Scientific
Model
Forma 3940
Chamber Volume
29 cu. ft.
Temperature Range
0°C to 60°C
Temperature Accuracy
±0.1°C (25°C–37°C)
Temperature Uniformity
±0.3°C (25°C–37°C)
Temperature Resolution
0.1°C
Humidity Range
Ambient to 95% RH
Humidity Accuracy
±5% RH
Humidity Readability
1% RH
Interior Dimensions
31" W × 27" D × 60" H
Exterior Dimensions
38" W × 32" D × 88.5" H
Electrical
208/220V, 60 Hz
Specifications are believed to be accurate but may vary depending on factory-installed options. Please verify all specifications prior to purchase.
Frequently Asked Questions
What is the Thermo Forma 3940 used for?
The Thermo Forma 3940 is primarily used for pharmaceutical stability testing, ICH storage studies, shelf-life testing, environmental simulation, biological incubation, agricultural research, and other applications requiring precise temperature and humidity control.
How is an environmental chamber different from a standard laboratory incubator?
Unlike a conventional incubator, an environmental chamber provides both refrigerated and heated operation while also controlling humidity. This allows laboratories to perform testing at temperatures below ambient as well as elevated temperatures under precisely controlled environmental conditions.
Can the Thermo Forma 3940 be used for pharmaceutical stability studies?
Yes. The Thermo Forma 3940 was designed specifically for applications such as ICH drug stability testing, controlled storage studies, and long-term pharmaceutical evaluation where precise environmental control is required.
What types of samples can be stored inside the chamber?
The chamber is suitable for pharmaceutical products, biological samples, packaged products, medical devices, plant materials, research specimens, environmental testing samples, and many other materials requiring controlled temperature and humidity.
Why purchase a refurbished Thermo Forma 3940 from American Instrument Exchange?
A refurbished Thermo Forma 3940 offers laboratories professional-grade environmental testing capabilities at a significant savings compared to purchasing new equipment. Every unit is inspected and tested prior to shipment and includes a 90-day warranty from American Instrument Exchange.
CLICK HERE to see the unused Thermo Forma 3940 refrigerated environmental chamber on our YouTube channel
Testing Procedures for Used and Refurbished Laboratory Incubators Ensure Quality and Stability Before Use
Used and refurbished laboratory incubators from American Instrument Exchange are thoroughly tested to ensure optimal performance and temperature stability with laboratory safety standards. Each unit undergoes a detailed inspection and functionality assessment to meet the needs of research, clinical, and industrial labs.
Why Testing Used Laboratory Incubators Is Essential
Before a laboratory incubator is reintroduced into any work environment, it must be tested for:
• Temperature uniformity and accuracy
• Airflow and humidity control (if applicable)
• Door seal integrity and insulation effectiveness
• Electrical and safety system compliance
Comprehensive testing reduces the risk of culture loss, contamination, and equipment failure—especially critical in applications involving cell culture, microbiology, pharmaceutical research, and diagnostics.
Our multi-point testing protocol for used and refurbished incubators ensures reliability, safety, and performance across all models and brands.
Key Testing Procedures for Refurbished and Used Laboratory Incubators
1. Initial Visual Inspection
• Check for cosmetic damage, corrosion, and wear to exterior surfaces, door hinges, and gasket seals
• Inspect power cord, wiring, and display panel for any defects or signs of tampering
• Confirm that shelves, chamber components, and internal fixtures are present and undamaged
2. Functional Testing
• Power on the incubator and verify all display indicators and alarms function correctly
• Test door latch and seal mechanisms for proper closure and insulation
• Run basic temperature cycles to ensure the unit maintains stability over time
3. Temperature Accuracy and Uniformity Tests
• Test internal sensors and controllers using temperature probes
• Measure temperature consistency at multiple chamber locations over several hours
• Confirm that programmable temperature settings respond accurately
4. Airflow and Humidity Control (if applicable)
• Test internal fan operation and airflow distribution
• For humidified incubators, inspect and test humidity reservoirs, sensors, and control systems
• Check for condensation buildup and confirm environmental stability
5. Electrical Safety and Compliance Checks
• Ensure all electrical components are properly grounded
• Perform insulation resistance and leakage current tests
• Verify compliance with current electrical safety standards for laboratory equipment
6. Final Quality Assurance Checklist
• Perform full cycle testing at various temperature setpoints
• Document performance benchmarks and results
All refurbished incubators from American Instrument Exchange are backed by our commitment to quality and precision. With our strict testing procedures, you can rely on your incubator to deliver dependable results from day one.
Repair and Refurbishment Protocol for Used Laboratory Incubators Performance and Quality from American Instrument Exchange
At American Instrument Exchange, every used laboratory incubator we sell goes through a repair and refurbishment protocol. Whether it’s a standard, CO₂, or refrigerated incubator, our goal is to restore each unit to laboratory-level performance—ensuring temperature accuracy, environmental stability, and long-term reliability in your lab.
Why Choose a Refurbished Laboratory Incubator from American Instrument Exchange?
• Fully tested for performance and safety
• Backed by a warranty
• Cost-effective alternative to new equipment
• Environmentally sustainable through reuse and restoration
• Refurbished by expert technicians with decades of lab equipment experience
Step-by-Step Refurbishment Protocol
Every incubator at American Instrument Exchange follows this comprehensive, multi-stage process:
1. Initial Intake & Inspection
• Visual inspection for cosmetic wear, corrosion, dents, or broken components
• Mechanical assessment of door hinges, gaskets, seals, and chamber components
• Document any missing parts or issues requiring repair or replacement
2. Cleaning and Decontamination
• Thorough internal and external cleaning using non-abrasive solutions
• Decontamination/cleaning of surfaces to remove biological, chemical, or particulate residue
• Cleaning of removable parts (e.g., shelves, trays, etc.)
3. Mechanical and Electrical Repair
• Repair or replacement of worn mechanical components such as door latches, fans, hinges, and seals
• Evaluation and repair of control panels, switches, thermostats, and displays
• Inspection and testing of wiring, fuses, relays, and power supplies
4. Environmental Control System Assessment
• For CO₂ incubators: CO₂ sensors, regulators, and gas delivery systems are tested
• For refrigerated incubators: compressors, condensers, and cooling systems are evaluated for performance and leaks
• Fan motors and airflow systems are tested to ensure uniform environmental conditions
5. Temperature and Sensor Testing
• All temperature sensors and controllers are tested using thermometers/probes
• Uniformity and accuracy tested at multiple chamber locations
• For humidified or CO₂ incubators, humidity and CO₂ stability are verified
6. Safety System Testing
• Test of over-temperature protection systems and alarms
• Evaluation of door sensors, safety interlocks, and power failure recovery
7. Final Quality Control and Documentation
• Full performance test run over 24 hours
• Validation of setpoints for temperature, CO₂ (if applicable), and humidity (if applicable)
• Final inspection and cleaning before packaging
• Complete service report
Trust the Experts at American Instrument Exchange
With over 50 years in the lab equipment industry, American Instrument Exchange is a trusted source for high-quality refurbished laboratory incubators. Our proven refurbishment protocol ensures every unit is reliable, accurate, and ready to meet the demands of your lab from day one.
Warranty Information
All used equipment sold by American Instrument Exchange is refurbished/reconditioned, tested to meet specifications, cleaned, and comes with a 90-day warranty from the date of shipment unless otherwise specified. New products include a warranty from the manufacturer. Your warranty is only valid if you have paid your invoice. If your invoice is over 30 days old, warranty work will not be performed until your invoice is paid in full. American Instrument Exchange is not liable for any special or consequential damages that result from the use of, or the inability to use, the materials on this site or the performance of the products,
Exceptions include international sales and items that are agreed to be sold with a lesser warranty or items that are agreed to be sold “as is.”
Should there be visible shipping damage to packaging or concealed shipping damage to item(s) supplied, buyer must communicate such damage to the delivering entity or carrier upon receipt first and to American Instrument the same day item is accepted / signed for. Failure to do so voids warranty. Customer decision to involve / procure third party or OEM service other than American Instrument or AIE assigned vendors to resolve in-warranty instrument failure or defect without first placing a service call to American Instrument voids warranty.
Return & Cancellation Policy
American Instrument Exchange will authorize the return of and issue a full refund for any equipment that is not working as represented and could not be replaced or repaired to the customer’s satisfaction by AIE or a representative of AIE during the warranty period. Returns without prior authorization and an RMA number will not be accepted.
Customers are responsible for proper packaging of the equipment and all included accessories. American Instrument will pay for insurance and shipping costs. Non-inventory items bought specifically to fill customer orders may possibly be returned, but on a case by case basis.
Customers who cancel orders after refurbishing has begun or after delivery where there are no equipment performance issues may be subject to a Restocking/Cancellation Fee of 20% or more and responsible for shipping costs for both the delivery and return.
Ongoing and Extended Support Options
American Instrument Exchange is able to provide additional repair and support services outside the warranty terms for most products that sell.
For biosafety cabinets, clean benches, chemical fume hoods, and other clean air products our team at AIE Laboratory Services can provide certifications, repairs, decontaminations, and other services for customers throughout New England, and guidance and limited technical assistance for any customers in the US and Canada for new or refurbished biosafety cabinets purchased from American Instrument Exchange.
For all other products, the repair service team at American Instrument Exchange can provide both field and depot repair evaluations. We can easily schedule and coordinate the pick-up and transportation of your malfunctioning equipment. By offering hourly rates lower than most OEM service providers and eliminating travel time for technicians, we help reduce repair costs. Furthermore, our lab depot repair service minimizes or eliminates scheduling delays. Our experienced service technicians are qualified to restore your equipment to factory specifications.
Yes, all equipment from American Instrument Exchange comes with a warranty. Used/reconditioned/refurbished equipment is tested to make sure it operates to the manufacturer's specifications and comes with a 90-day warranty (unless otherwise noted). New equipment comes with a warranty from the manufacturer.
How do you test and recondition the equipment?
Testing requirements vary across all the equipment categories we sell. Temperature controlled units are tested with NIST traceable probes and data loggers. Gaskets, external housing, glass, handles, controls and control screens are all thoroughly inspected for integrity and functionality. We test all equipment using the manufacturer's parameters and specifications to confirm that the unit operates properly.
How do products ship from American Instrument Exchange?
We can ship products both nationally and internationally using a well-established network of transporters. Smaller items will ship via UPS. Larger equipment will be palletized and shipped either LTL or air-ride, depending on the specific equipment and/or delivery requirements.
Return and order cancellation policy
American Instrument Exchange will accept the return of any product that is not working as represented and could not be replaced or repaired to the customer's satisfaction during the warranty period. Customers who cancel orders after refurbishing has begun will be subject to a cancellation and restocking fee of between 20% and 40%.
Are discounts available for educational or non-profit institutions, or for bulk purchases?
Yes – call or email us today with a list of equipment you're looking for and we can potentially put together a quote that includes a discount.
How does your price matching policy work?
We strive to keep our pricing competitive and reasonable. If you find comparable items for sale at a lower price from other vendors please send us a link and or quote for the item and we'll do our best to match or beat the price.
Can I see the equipment in person before committing to a purchase?
Customers are welcome to make an appointment to view equipment in our warehouse. Given our workload we may not be able to test or clean the equipment prior to your arrival if you have not committed to an order.
1023 Western Avenue is a working warehouse, not a showroom, and customers should dress appropriately and wear closed toe shoes.
Can I ship products that I purchased elsewhere to American Instrument for repair?
Yes – please see our repair services page for more information.
