Pro 4 Warn Plus Alarm Analyzer


The Pro 4 Warn combines three gas analyzers—oxygen (O2), carbon monoxide (CO), and carbon dioxide (CO2)—a moisture monitor (H2O), a high-temperature sensor plus a flow meter into a single water-resistant box. Abnormal readings activate audible and visual alarms; an optional relay can shutdown equipment or sound external alarms when temperature or gases reach unacceptable levels. Two power options available. Choose from 110/210V wall plug-in or rechargeable lithium battery with charger. Pro H2O Moisture Probe Sampling Manifold not included.


The Nuvair Pro 4 Warn is a multigas, multifunction alarm analyzer that is mounted in a water- and impact-resistant case with a clear cover that allows for viewing of all gas displays and visual alarms. There is easy external access to analyzer controls that are compatible with outdoor and marine environments.

The analyzer is powered by a standard wall plug-in. The optional lithium battery that can independently operate the analyzer for 3-4 hours. The analyzer uses a flow restrictor to deliver sample gas to the sensors as pressurized gases must be regulated down to avoid damage to the sensors.

The Pro 4 Warn is equipped with audible and visual alarms for high temperature and user-programmable low and high threshold gas (CO, CO2 and O2) content plus a flow meter. If the alarm sounds, the analog output can activate an optional relay that shuts down compressors automatically, sounds a remote alarm, or activates emergency backup systems.

WARNING: Never expose gas sensors to pressure or you may cause damage and/or false readings. Damaged sensors will not provide accurate gas analysis. Most gas analyzers can be used to analyze a regulated gas sample flow, the contents of a gas cylinder, or the flow from a regulator. The flow rate of gas must equal 1-5 L/min. To produce this flow, a Flow Restrictor and Regulator may be required. A faulty Flow Restrictor can lead to a false analyzer reading. Flow Restrictors should be regularly tested with a Flow Meter. Inaccurate gas analysis can lead to serious personal injury or death.


  • Programmable alarm thresholds
  • Audible and visual alarms
  • Fast response
  • High temperature switch
  • Compact water-resistant container
  • Designed to test breathing gases
  • Easy to operate
  • Reliable and accurate
  • Optional relays for external alarm or compressor control


  • Audible and visual alarms for oxygen (O2), carbon monoxide (CO), carbon dioxide (CO2), moisture (H2O) & high temperature
  • On/Off buttons for individual monitors
  • Temperature compensated sensors
  • User replaceable batteries and sensors
  • Low battery warning indicator
  • Factory reset

CO2 Analyzer

  • 50 ppm resolution from 0 to 1000 ppm, then 100 ppm up to full scale
  • 0-2000 ppm range

Moisture Monitor

  • Audible visual alarms for high moisture content in filters
  • Warning light for filter changes
  • Sampling manifold not included

High Temperature Alarm

  • Audible and visual alarms for high temperatures at the final stage
  • Relays to shutdown compressor

O2 Analyzer

  • 0-100% range oxygen monitor
  • 36-month electrochemical sensor
  • ±1% accuracy

CO Analyzer

  • 0-100 ppm range CO monitor
  • 18-month electrochemical sensor
  • ±1% accuracy

Flow Meter

  • 0-10 L/min meter
  • 4 L/min maximum flow rate

Replacement Sensors