Testo 0390 0118 Replacement Co Sensor 0-4000 Ppm

Product Description

The TESTO 0390 0118 is a replacement carbon monoxide (CO) measuring cell designed for use in combustion and flue gas analysis equipment. This sensor operates without hydrogen (H2) compensation, meaning it measures CO concentration directly without correcting for cross-sensitivity to hydrogen gas. It covers a measurement range of 0 to 4000 parts per million (ppm), making it suitable for a wide range of combustion efficiency and safety testing applications. Licensed HVAC technicians and combustion analysts install this cell as a consumable replacement when the existing sensor reaches end of service life.

This CO sensor is intended for use in the Testo 330-1 LL flue gas analyzer. Flue gas analyzers are used during commissioning, seasonal servicing, and compliance checks on gas-fired furnaces, boilers, water heaters, and other combustion appliances in residential and light commercial settings. The sensor plugs into the analyzer to restore accurate CO measurement capability after the original cell degrades.

Key Features

• Measurement range of 0 to 4000 ppm CO for broad combustion testing coverage
• No H2 compensation — straightforward CO detection without hydrogen cross-sensitivity correction
• OEM-style replacement cell engineered for the Testo 330-1 LL analyzer platform
• Restores full CO measurement function when the installed sensor reaches end of life
• Electrochemical cell design standard to portable flue gas analyzer applications

Compatibility

Designed as a direct replacement CO measuring cell for the Testo 330-1 LL flue gas analyzer.

Installation Notes

CO sensor replacement in flue gas analyzers is typically performed by HVAC technicians or combustion specialists familiar with the analyzer's service procedures. Power down and fully purge the analyzer before removing the old cell, following the manufacturer's sensor replacement guide. Handle the electrochemical cell carefully to avoid physical damage or contamination of the sensing element. Consult the analyzer's service documentation for proper seating and connection confirmation before returning the unit to service.

Technical Specifications

• Measurement Range: 0 to 4000 ppm CO
• H2 Compensation: None
• Application: Flue gas analysis

Standard Information

• Brand: TESTO
• Manufacturer Part Number: 0390 0118