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VELIT LAMBDA AFR
VELIT LAMBDA AFR
Description

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

Combustion Monitor & Closed-Loop Controller

VELIT LAMBDA AFR

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

Regular price $249.00
Sold out
  • 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.

USA Location Inventory Status

In Stock

Reach out to contact@velitcamping.com for restocking time

“The check engine light your heater never had.”

Quick Start GuidePDF
Ships from the US
2-year warranty
Install support
Description

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

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VELIT LAMBDA AFR
Regular price $249.00
Sold out
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.

Cold mornings are the worst time to find out your heater has drifted.

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.

Read the exhaust

One number. A lot of information.

1.38Lambda, live from the exhaust
1.38
Rich ← 0.8 Optimal 2.2 → Lean
Diesel heaters 1.0 – 1.6
Gasoline heaters 1.2 – 1.8

Too rich

Carbon buildup, soot, black smoke and shorter service intervals.

Optimal

Clean combustion, stable operation and improved reliability.

Too lean

Unstable combustion, hard starting and flameout risk.

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
CombustionInside the heater
O₂ sensorWideband, in the exhaust
LambdaMeasured air-fuel ratio
Heater ECU6.X firmware
Fuel adjustmentCorrected automatically
Back to combustion — continuously
Compatibility

One product. Two ways to use it.

Capability Any gasoline / diesel heater Compatible Velit heater
Real-time lambda reading Supported Supported
Rich / lean diagnosis Supported Supported
Installation verification Supported Supported
Pre-season health check Supported Supported
Maintenance diagnosis Supported Supported
Closed-loop AFR control Not supported Supported
Automatic altitude compensation Not supported Supported
Smart Priming Not supported Supported
Smart Ignition Not supported Supported
Everything you need

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

Questions

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 lambda 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 Lambda compensate for a bad installation?

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

Does the sensor stay permanently installed?

It can be connected at any time. For accurate readings, wait at least five minutes after starting the heater or changing the power setting.

Plug it in. Read it. Know.

Check your heater before winter — not on the coldest morning of the year.

Compatibility
Documentation

Manuals & guides

Everything you need to install, configure and service your Lambda AFR.

Velit Lambda AFR — User Manual

Installation, wiring, lambda targets and troubleshooting.

PDF
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