Model NU-8631 is a CO2 Incubator featuring an Oxygen monitoring and control system to suppress Oxygen levels in the growth chamber by injecting Nitrogen for hypoxia research. Temperature is control by using dual temperature sensor probes heating water surround the growth chamber for a more stable environment.


An incredibly accurate incubator, the In-VitroCell™ ES NU-8631 provides the perfect environment for hypoxic research applications. Features such as an easy-to-use interface, top-notch filtration and constant monitoring of chamber conditions give labs both large and small the assurance that their samples will be protected.

Constant Contamination Control

Closed-Loop HEPA Filtration

The best of both worlds bring together the standards of an ISO Class 5 Clean Room and a space-saving footprint. The ES NU-8631 offers a contamination-free environment through the use of slightly positive pressure, preventing contaminated room air from entering the growth chamber. Also, both gas and air are continuously passed through the unit's 99.99 percent efficient HEPA filters to ensure a contaminant-free growth chamber. Cell desiccation is minimized with less frequent air changes at intervals of every 20 minutes.

Coved Interior Corners

Every NuAire CO2 incubator is designed with a crevice-free chamber interior, including smooth and rounded corners to improve cleaning and eliminate areas where contaminants can lurk.


NuTouch Electronic Control System (ECS)

All NuAire CO2 incubators come standard with a 5x7 inch (127 by 178 mm) color touchscreen. Additionally, it comes available in four different languages, including English, German, Spanish and French.

With the touch of a finger, system parameters and set points can be updated, carbon dioxide and temperature history graphs viewed or data downloaded via USB. System statuses are conveniently shown on screen while the incubator sensor is sampling air, the unit is performing chamber adjustments, or the unit is in standby mode.

Sensitivity and Accuracy of Gas Control

To monitor and adjust CO2 levels within the growth chamber, the incubators include a sensor bay that contains a highly accurate, non-dispersive, microprocessor-based, single-source dual-wave infrared (IR) sensor that uses wavelengths absorbed only by CO2, which makes it impervious to elements such as water vapor.

The result is CO2 levels with an accuracy of ±0.1 percent, an incredibly stable output with minimum drift, allowing for less frequent calibrations. Gas levels are controlled by the injection of nitrogen into the chamber to suppress O2, offering accuracy to +-0.25 percent with a range of 0.5 - 21 percent.


Temperature Uniformity

To ensure the most uniform inner chamber temperature, the unit is heated using circulating water that flows around the growth chamber, offering a temperature accuracy of ±0.1 °C.

Heat Recovery

A more stable environment is maintained through the quick recovery of heat at 0.12 °C per minute. The set point of 37 °C can be recuperated after a 30-second door opening within 15 minutes.

Humidity Control

Maintaining humidity is never an issue with any NuAire CO2 incubator. A relative humidity level of up to 95 percent can be achieved in the growth chamber through the use of distilled or demineralized water in the stainless steel pan that sits in the bottom of the chamber.

Standard Features

  • 16-Gauge Type 304 Polished Stainless Steel Growth Chamber
  • 16-Gauge Type 304 Polished Stainless Steel Shelving (Qty 4)
  • NuTouch Electronic Control System (ECS)
  • Closed Loop HEPA Filtration System
  • Infrared (IR) Sensor
  • O2 Monitor and Control System
  • R5 Insulation System
  • Independent Door Heater
  • Right Hinge Swing Field Reversible Exterior Door
  • Right Hinge Swing Field Reversible Inner Glass Door
  • Removable/Autoclavable Inner Door Gasket
  • Water Fill Port
  • Drain Valve
  • Quantity Four (4) Shelves
  • Quantity Four (4) Wall Brackets
  • Quantity Eight (8) Shelf Guides
  • Heavy Duty Leg Levelers
  • USB Port
  • RJ-11 Communication Port for Remote Alarm Connection
  • RJ-45 Jack - RS-485 2-way Communication
    • Output: Control system levels and alarms/events
    • Input: Commands from a Computer to view and update operating parameters
  • RJ-45 Jack - 4-20 mA Analog Output for monitoring all active control system levels
  • Utility Access Port
  • Stainless Steel Water Pan
  • 8-foot (2.5 m) electrical power cord
  • Field Stackable with Appropriate NuAire Incubator Models



Part Number Description
8631I60 Stainless Steel Chamber
8631I61 Stainless Steel Chamber with Cooling Coil


Part Number Description
8631I54 Stainless Steel Shelving (Qty 4)
8631I45 Copper Shelving (Qty 4)



Electrical Requirements
Models NU-8631: 115 V, 50/60 Hz
NU-8631E: 230 V, 50/60 Hz
Quality Assurance UL, UL-C, CE


Exterior Dimensions (W x D x H) 25.625 x 27 x 37.75 in
649 x 685 x 958 mm
Foot Print (W x D) 22 x 17.5 in
557 x 445 mm
Interior Dimensions (W x D x H) 20.375 x 20.625 x 24 in
518 x 524 x 611 mm
Chamber Volume 5.65 ft3
160 Liter
Shelf Dimensions (W x D) 18 x 18.75 in
457 x 476 mm
Shelves Supplied (Standard) Quantity 4
Maximum Shelf Capacity 16
Maximum Weight Capacity 25 lbs (11.34 kg) per shelf
125 lbs (56.7 kg) per incubator
Water Pan Dimensions (W x D x H) 10 x 1.5 x 12 in
254 x 38 x 305 mm
Water Pan Capacity 2 Liters (Maximum)
1.5 Liters (Recommended Fill)
Volume 5.65 ft3
160 L
Net Weight (Including Water and Shelving) 403 lbs
183 kg


Temperature Control
Control Range 5 °C above ambient (to a 30 °C max ambient) to 55 °C
Set-Point Range 5 °C to 55 °C (37.0 Default)
Uniformity ±0.2 °C @ 37 °C
Accuracy ± 0.1 °C
Recovery 0.12 °C/min. on Average
Display Resolution 0.1 °C
Door and Perimeter Heater Control Logic Proportional base duty cycle based on Temperature set point and 0-100% manually adjustable to adapt to ambient conditions.
Temperature Sensor Type Precision Integrated Circuit


CO2 Control Standard
Range 0.1 to 20% (default 5%). (0.0 set point idles system)
Accuracy ±0.1%
CO2 Recovery Up to 5% ±0.2% / -0.5 in 5 minutes Average
CO2 Display Resolution 0.1%
CO2 Control Logic Fixed Algorithm/Manual, Environmental Adaptable
CO2 Sensor Type Infrared single source dual wave length


Oxygen Display and Control
Control Range 0 to 25%
O2 Set-Point Range 0.5 to 21%
Default Set Point 21%
O2 Accuracy ±0.25%
O2 Recovery 5% ±2%: 15 minutes on average