VELIT Lamda AFR Combustion Monitor + Controller for Gasoline & Diesel Heaters

For gasoline & diesel air heaters. Know how your heater is running. Before it stops running.

• Works with virtually any gasoline or diesel air heater.
• Check combustion condition directly from the exhaust.
• Identify rich or lean operation before problems occur.
• Unlocks closed-loop control on compatible Velit heaters.

Combustion Monitor & Closed-Loop Controller for Gasoline & Diesel Heaters

Know how your heater is running before it stops running.

VELIT Lambda AFR gives your heater real-time combustion feedback, helping you detect rich or lean operation, diagnose performance issues, and maintain reliable heating. Simply connect it to the exhaust to check combustion health.

For compatible VELIT heaters, Lambda AFR enables closed-loop combustion control, automatically adjusting fueling for improved stability, cleaner operation, and better reliability at changing conditions.

Features:
✓ Real-time Lambda monitoring
✓ Rich / lean combustion diagnosis
✓ Pre-season heater health checks
✓ Installation and maintenance troubleshooting
✓ Closed-loop AFR control for compatible VELIT heaters
✓ Smart Priming & Smart Ignition support

The problem - Your heater keeps running. Until it doesn’t.

Most air heaters operate open-loop. They follow preset fueling parameters without knowing how well the heater is actually burning. Altitude, temperature, fuel delivery, installation and carbon buildup can all change combustion over time. Without combustion feedback, you often don’t know there’s a problem until the heater becomes difficult to start—or doesn’t start at all.

Lambda is the check engine light your heater never had.

What it does - Combustion feedback, finally.

• Real-time combustion monitoring - See how your heater is actually burning in seconds.
• Rich / lean diagnosis - Know if your heater is running rich or lean.
• Installation check - Verify fuel, intake and exhaust installation.
• Pre-season health check - Check your heater before winter or a major trip.
• *Automatic altitude compensation - Automatically adapts to changing combustion conditions at elevation.
• *Closed-loop control - Continuously adjusts fueling for optimal combustion.

* Requires a compatible Velit heater with 6.X firmware.

Exclusive to compatible Velit heaters

The world’s first closed-loop air heater system.

Lambda doesn’t just tell you how your Velit heater is running—it allows the heater to continuously correct itself.

Measure. Adjust. Verify. Repeat.

• Improved efficiency and stability
• Reduced carbon buildup
• Longer service intervals
• Smart Priming & Smart Ignition
  

What’s in the box

• Heated wideband oxygen sensor
• Lambda / AFR analyzer module
• Sensor adapter / base
• Velit heater harness
• 12V cigarette-lighter power harness
• Rubber L-joint for exhaust-cap installations
• Installation hardware

FAQs

Will this work with my heater?

Yes. Lambda works as a standalone combustion monitor on virtually any gasoline or diesel air heater. The sensor connects to the exhaust and the module shows the live lambda reading.

Do I need a Velit heater?

No. Any heater can be measured and diagnosed. A compatible Velit heater running 6.X firmware adds closed-loop control, Smart Priming, Smart Ignition and automatic altitude compensation.

How do I use it with another heater brand?

Thread the sensor into the included adapter, insert the adapter into the exhaust pipe (or use the rubber L-joint for exhaust caps), and power the module from the 12V cigarette-lighter harness.

What lamda should my heater run at?

Diesel heaters typically run 1.0–1.6 and gasoline heaters 1.2–1.8. Recommended targets vary slightly between heater brands and combustion-system designs.

Can the VELIT Lamda compensate for a bad install?

The adaptive system compensates for minor variations, but it does not replace proper fuel, intake and exhaust installation.

Does the sensor stay permanently installed?

No, but it can be connected at any time. For accurate readings, wait at least five minutes after starting the heater or changing the power setting.