Real-time monitoring
See current and total fuel consumption without waiting for the next refuelling.
Electronic fuel monitoring instruments
Know exactly how much fuel you use.
Flowtrecs displays fuel flow, consumption and key engine operating parameters — clearly, in real time and right where you need them.
FT / 01
Current fuel flow
0.0 l/h
Model
INOX
Stainless steel · GPS · Waterproof IP65
For internal combustion engines
- Petrol
- Diesel
- Heating oil
01 — Better information
Don’t guess.
Measure.
Fuel consumption varies with speed, load and operating conditions. Flowtrecs turns flow measurements into data you can use immediately.
Fuel economy in km/l
Combining consumption with speed shows how many kilometres you travel per litre — depending on the model.
A system matched to your engine
Different sensor versions allow the measurement to be matched to the actual flow rate in your fuel system.
Fuel economy
More kilometres.
Less spent on fuel.
Flowtrecs helps you find settings that let you cover the same distance with less fuel. Fewer litres burned simply means less money spent on fuel.
Fuel consumption does not rise in direct proportion to speed. A small change in RPM, trim or weight distribution can noticeably alter the distance available from the same amount of fuel.
Inox, Mini, Wave, Android BT, C7 Ultra and App combine actual consumption with speed and show fuel economy. The skipper can compare settings underway and look for the operating point with the highest km/l value.
Learn how to use the km/l readingExample
32.0km/h
16.0l/h
Fuel economy
2.0 km/l
speed ÷ consumption
Same route · 60 km
at 1.5 km/l40 l
at 2.0 km/l30 l
10 fewer litres needed for the same route
- 01
Maintain safe, steady conditions.
- 02
Change one parameter at a time.
- 03
Compare km/l and choose the best setting.
Figures are illustrative calculations. Actual savings depend on fuel price, conditions and how the boat is operated. The reading alone does not reduce consumption — it gives the skipper real data for better decisions.
02 — The Flowtrecs range
One family.
Different solutions.
From a compact gauge to a touchscreen panel, an app and a flow sensor. Select a solution to see its key features.
01
Flush-mounted gauge
Flowtrecs Inox
A compact waterproof IP65 fuel computer for one petrol engine. It supports a maximum of one FS-40 sensor.
- Waterproof · IP65
- GPS
- 2″ LCD
- Max. 1 sensor
03 — How it works
From the fuel line to an informed decision.
The system measures actual fuel flow, processes the data and displays it on the selected screen. No estimates based on the fuel level gauge alone.
Help me choose a system-
01
The sensor measures fuel flow
Size the FS-40 for minimum and maximum flow in its line. For a diesel with return, use circulating flow, not fuel burn alone. How do I choose the sensor range?
-
02
The system processes the data
The signal is converted into current and total fuel consumption, fuel economy and the other values available in the selected model.
-
03
You see a clear result
The reading shows how changes in speed or boat settings affect fuel consumption and fuel economy in km/l.
04 — Applications
Wherever flow
matters.
Selected Flowtrecs solutions measure petrol, diesel fuel and heating oil, so their applications extend beyond the water.
Agricultural machinery
Tractors, combine harvesters and other machinery powered by internal combustion engines.
Generator sets
Monitoring operation and fuel consumption in stationary equipment.
Light aviation
Microlights and light aircraft powered by internal combustion engines.
Heating systems
Oil flow monitoring in burners and heating systems.
05 — Knowledge base
Clear answers.
Better decisions.
Practical guidance on FS-40 installation, sensor selection and diesel fuel measurement, plus app and Bluetooth setup.
View all guides
How to install the Flowtrecs FS-40 correctly
Horizontal mounting, correct flow direction, the right fuel hose and careful bleeding all affect system integrity and stable readings.
Read guide
Flowtrecs calibration and troubleshooting, step by step
If a reading is missing, unstable or consistently differs from verified consumption, inspect the installation first.
Read guide
How does diesel fuel measurement work, and which sensors do you need?
Trace every return branch, choose a 2- or 4-sensor kit and check each line's lower and upper flow limits.
Read guide06 — FAQ
From installation.
To reliable readings.
Six essential answers about selection, installation, calibration, power and purchasing. Detailed instructions are available in the knowledge base.
How many FS-40 sensors do I need?
One petrol engine without a return line normally needs 1 sensor, while two such engines need 2. One return-line diesel engine needs 2 sensors, one on the supply and one on the return, while two such engines with separate return circuits need 4. Inox and Mini support a maximum of 1 sensor; the appropriate Wave, Android BT, C7 Ultra and App variants support 1, 2 or 4. See the sensor-count guide for the full configurations.
How do I select the correct FS-40 sensor range?
Select each sensor so its lower and upper limits cover the minimum and maximum actual flow in that specific line, not engine power or net fuel consumption alone. On a diesel, check feed and return separately; pump data is a starting point, not a substitute for operating flow. Include permitted feed restriction and return backpressure. If data is missing, send the installation details; the FS-40 page and diesel selection guide will also help.
Where and in which position should the sensor be installed?
Mount the sensor securely and horizontally, with its arrow pointing in the direction of fuel flow, away from excessive engine heat and vibration. The fuel filter should be upstream of the sensor; after installation, fill and bleed the system and check it carefully for leaks. Refer to the FS-40 installation guide for model-specific details.
Does Flowtrecs require calibration?
Fuel-consumption measurement kits with FS-40 sensors are supplied factory-calibrated and configured for the ordered version. There is no need to calibrate the device yourself or select the sensor type, range or count. Android BT and C7 Ultra kits come with the display already paired with the Bluetooth module. Only the App version requires you to pair your own Android phone or tablet after correct installation. If the readings need checking, follow the calibration and troubleshooting guide.
Can the device use a 24 V supply and is it waterproof?
Flowtrecs systems are intended for a nominal 12 V installation; the exact input range depends on the model. Do not connect a unit directly to 24 V — confirm an appropriate regulated converter with Flowtrecs first. Inox is waterproof (IP65), Mini splash-resistant (IP64), Wave waterproof (IP68) and C7 Ultra waterproof (IPX6). The standard 7-inch Android BT panel is not waterproof and must be installed only inside an enclosed boat, in a dry cabin or at a fully protected indoor helm. With App, water protection depends on the phone or tablet. Compare the models before choosing the installation position.
Where can I check the price, availability and shipping cost?
Prices, stock, supported countries and delivery charges can change, so the current store and checkout provide the binding information. English and German customers should use the appropriate language version of shop.flowtrecs.com. If a country or delivery method is unavailable at checkout, contact the store before placing the order.
System selection
Tell us about
your engine.
Provide the engine model and count, fuel type, return-line layout and — if known — pump flow. We will help select the right model, sensor count and measuring range.