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The Testo 300LL Longlife is built for the demands of commercial heating system installation, commissioning and maintenance. Its O2 and CO sensor combination uses hydrogen compensation and can measure up to 30,000ppm via automatic fresh air dilution, without needing extra flue probes or complicated setup.
The sensors are rated for up to 6 years of service life, and with product registration, they're covered by a manufacturer's warranty of up to 5 years — no maintenance contract required. This sits well beyond the domestic-focused Testo 300+ range, both in CO measurement range and sensor longevity, making it the better fit for intensive daily commercial use across multiple sites.
An optional NO sensor can be retrofitted later for NOx measurement, so the capability can be added without replacing the analyser. The 5-inch smart-touch HD display offers responsive touchscreen operation with structured measurement menus, and Bluetooth/WLAN connectivity allows up to four Testo Smart Probes to be connected for parallel measurement, plus direct report emailing via WLAN hotspot.
Integrated draught and gas zeroing means the flue probe doesn't need to be removed from the flue during zeroing, and a quick-change probe system accepts a range of probe shafts for different applications and pipe sizes. It's EN 50379 Parts 1-3 compliant and TÜV-tested to the German Federal Immission Control Ordinance (BImSchV) standards.
A CO range of 30,000ppm via automatic fresh air dilution, combined with 6-year sensor life, sets this apart from the domestic-focused Testo 300+ range and reflects what's actually needed for intensive commercial use across multiple sites. An optional retrofittable NO sensor means NOx capability can be added later without buying a new analyser, and integrated draught and gas zeroing without removing the probe keeps testing efficient during a busy service round.
Order the Testo 300LL Longlife Flue Gas Analyser Standard Kit online today.
| Brand | Testo |
|---|---|
| Product Type | Flue Gas Analyser – Longlife Standard Kit |
| Oxygen (O2) | 0 – 21 Vol.% |
| Carbon Monoxide (CO) | 0 – 30,000ppm, H2-Compensated with Auto Fresh Air Dilution |
| Ambient CO (Internal Probe) | 0 – 2,000ppm |
| Ambient CO (External Probe) | 0 – 500ppm |
| NO (Optional, Retrofittable) | 0 – 3,000ppm |
| Draught | -9.99 to +40hPa (Accessory Required) |
| Pressure | -100 to +200hPa (Accessory Required) |
| Temperature | -40°C to +1,200°C (Accessory Required) |
| Efficiency | 0 – 120% |
| Flue Gas Loss | 0 – 99.9% |
| CO₂ | Digital Calculation to CO₂ Maximum |
| Standards | EN 50379 Parts 1-3, TÜV-Tested to BImSchV |
| Display | 5.0" HD Smart-Touch Display |
| Connectivity | Bluetooth and WLAN – Up to 4 Smart Probes |
| Memory | 1 Million Measuring Values Plus Address Book |
| Sensor Life | Up to 6 Years (O2 and CO) |
| Battery Life | Up to 10 Hours (Approx. 1 Week at 2hrs/Session) |
| Warranty | Up to 5 Years on O2/CO Sensors with Product Registration |
