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Product Spotlight: Testo 327-1 Flue Gas Analyser

Unveiling the Efficiency and Reliability of the Testo 327-1

In the world of domestic boiler servicing and commissioning, the Testo 327-1 Flue Gas Analyser emerges as a standout choice for gas engineers. This device not only epitomises reliability and user-friendliness but also aligns with essential industry standards like EN 50379 and BS7967. In this review, we will delve into its features, functionality, and overall performance.

Design and Build Quality

At first glance, the Testo 327-1 impresses with its ergonomic design. The robust construction, coupled with a tough rubber over mold, ensures durability against the daily wear and tear of fieldwork. Its magnetic rear is a thoughtful addition, allowing easy attachment to boiler casings for hands-free operation. Moreover, the analyser’s included firm soft carry case with a shoulder strap enhances portability and ensures safe storage and transportation.

Display and User Interface

One of the most striking features is its 4-line LED display, which stands out for its clarity and back-lighting function, ensuring readability even in poor lighting conditions. The display can show up to four parameters simultaneously, providing real-time measurements that are crucial during boiler servicing. The menu navigation is intuitively designed, making it easy to access various features and settings.

Performance and Capabilities

The Testo 327-1 is equipped to measure key parameters such as O2, CO, and temperature. It can also calculate the ratio, CO2, and efficiency – all crucial for assessing a boiler’s performance. The device’s capability to handle flow and return temperature measurements, along with a comprehensive pressure menu, adds to its versatility. Notably, it can accommodate seven different fuel types, including a hydrogen blend up to 20%, making it a future-proof investment.

Advanced Protection and Durability

One of the key strengths of the Testo 327-1 is its built-in protections. The automatic pump protection is a vital feature that prevents damage to the CO sensor due to overexposure. This protection, along with a 4,000ppm CO sensor range, is critical for maintaining the device’s longevity. Additionally, the built-in condensate trap, designed for easy emptying, minimizes the risk of water ingress into the unit.

Battery Life and Charging

The inclusion of a rechargeable Li-ion battery is a significant advantage, ensuring long-lasting performance suitable for extensive fieldwork. The battery life, coupled with the convenience of recharging, makes the Testo 327-1 a reliable companion for day-long operations.

Additional Features

The Testo 327-1 also includes tightness and let-by pressure test routines in its menu, enhancing its utility for thorough boiler inspections. However, it requires a pressure connection adaptor for these tests. Additionally, the option to measure flow and return temperatures with additional accessory probes further extends its functionality.

Service and Calibration

As an approved Testo distributor and service centre, Test4less offers yearly calibration services, ensuring the device remains accurate and compliant with manufacturer specifications. This service also protects the instrument’s warranty, an essential aspect for long-term use.


The Testo 327-1 Flue Gas Analyser is a robust, efficient, and user-friendly tool tailored for domestic gas engineers. Its range of features, coupled with its durability and ergonomic design, make it an excellent choice for daily use in boiler commissioning and servicing. While it requires additional accessories for certain tests, its versatility and reliability make it a valuable investment for professionals in the field.

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