Optio Fuel Frequently Asked Questions:
Where can I get an Optio Fuel sensor?
Optio Fuel is available through select marine dealers and on our web store at https://shop.interactio.co. Note: all prices are shown in Canadian dollars so cost is less expensive if you are in a country with a favourable exchange rate.
How does EcoRange work?
The Interactio Smart Boat App displays your fuel flow/consumption and a map indicating your range at current consumption and a green EcoRange circle. The EcoRange is calculated based on the averages of your last three trips. Adjust the throttle(s) up or down (usually down a bit) until your range circle lines up with the green EcoRange circle and that’s it - you are now running at the optimal speed to maximum range for minimum fuel.
How do I install it?
The fuel sensor does not need to be wired, so it is as easy as locating convenient access to your fuel line. The Optio Fuel sensor comes with two barbed connections for 1/4", 5/16", 3/8" or 1/2" standard marine fuel line. Simply empty your fuel line, cut the line and connect the two ends onto the fuel sensor's barbed fittings, tighten the hose clamps and you are done. Download the Interactio Smart Boat app from the Apple App store, sync it with your installed sensor and start saving money! Android App coming soon...
Can Optio Fuel handle fuel return lines on Diesel engines and HPDI gasoline engines and if so, how?
Yes. On engines where return lines are used a second Optio Fuel is installed in the return line from the engine to the tank(s). When setting up the app simply set the toggle to "This is a return line" and fuel returned is automatically subtracted from what was supplied. The app range calculations, optimal economy, totalizer and remaining fuel is automatically updated.
How many engines can Optio Fuel support?
The Smart Boat app can currently handle 3 engines - Port, Centre and Starboard with both Supply and Return for each engine. If you have quad engines please call us at 1-877-304-9476.
How many sensors will I need for my boat?
For a single gasoline engine with no return (Outboards, gasoline inboard/outboards) you need a single Optio Fuel.
For twin gasoline engines with no returns (twin outboards, twin I/Os) you will need two Optio Fuel sensors - one for each engine. A discounted bundle is available for two sensors
For twin Diesel engines or engines with fuel return lines you will need four Optio Fuel sensors - one for each supplies and one for each return, two per engine, four total. A discounted bundle is available for four sensors
If you have twin engines, you can choose to install Optio Fuel on only one Engine and essentially double the flow numbers and half the range to save money. Although this will work, it does not give you visibility into the performance of each individual engine, and most often twin engines perform slightly different. It also means you will have to "do the math" instead of the app, but it will work.
How is Optio Fuel powered?
Optio Fuel is powered by a CR2450 battery that can be easily changed. Due to the low power draw of Bluetooth Low Energy (BLE) devices the battery will not need to be serviced very often, usually not more than once a year.
These batteries are available at most retail stores like Camera shops, Pharmacies and even Grocery stores. they are quite common and cost about $4 to $8 CDN.
How long will the battery last?
The sensors have been tested to run for over 1700 hours of continuous fuel flowing operation on a single CR2450 coin cell lithium battery. They go to "sleep" two minutes after fuel stops flowing, but they will still use a small amount of power while sleeping. The battery will last approximately 330 days in sleep mode. The App has a battery strength indicator and shows the battery voltage in millivolts.
The average boater uses their boat 200 hours of run time per year so the design intent is to change the battery once a season. To replace the battery, the top cover comes off with 4 screws to reveal the water-tight, o-ring sealed battery compartment. Changing the battery takes about 5 minutes.
How much does Optio Fuel cost?
Optio Fuel consists of a fuel flow sensor kit and free App. The kit includes everything you need to install it including stainless steel clamps for double-clamp installation, stainless mounting screws with sealing washers, o-ring sealed hose barbs and a battery.
Optio Fuel costs approximately 60-65% of the competition and has no wiring so is considerably less expensive to install than other options. It uses your existing smartphone or tablet for a display so there is no need to install special gauges, panels or multi function displays.
Single sensors and multi-sensor bundles are available on our online Shop
How much can Optio Fuel save?
The numbers will vary depending on your boat, how often you use it and what your cruising style is, but you can expect the savings to be from 10% on the low side to upwards of 30% or more. Without engine fuel management, RPM, fuel consumption and boat speed are hard to gauge and in many cases are approximate at best. In our tests, even for those who pay close attention to their cruising speed, engine RPM, current, wind and tides 10% is realistic. More often we have found that boaters are not as aware of these factors or do not bother with it - they throttle up until they reach the speed they want and leave it at that. Our calculations are conservative - we have shown numbers for a smaller, single engine vessel. The savings will be significantly higher if you have twin engines and a bigger boat. Here are the numbers from our test boat:
23ft Bayliner Trophy with 200 HP Suzuki DF200TX 4 Stroke 6 cylinder outboard engine: consumption is 18 US gph @ 5600 RPM wide-open throttle (WOT)
On a typical day’s cruise:
Running with the throttle at 75% test boat uses 14.25 US gph. We ran for 6 hours, using 85.5 US gallons (14.25 gph x 6 hrs). At an average marine gasoline price of $3.60/gallon, this equals over USD $307 per cruise…
At 10% savings this is over $30 per day! At 20% it's $60, at 30% $90, etc. and this is at an average fuel price. If you are in an area where fuel is more expensive the numbers are even higher.
As you can see it doesn't take long for Optio Fuel to pay for itself!
Where is Optio Fuel made?
Optio Fuel is manufactured in North America (Victoria, BC, Canada). All design, engineering and testing are done locally by us.
Where can the Optio Fuel be physically installed on my boat?
The Optio Fuel sensor should be mounted downstream (after) your fuel filter to ensure that debris does not clog the sensor. Ideally the sensor should be mounted on a vertical surface like this:
Although the sensor will work in a horizontal orientation (like lying "flat" on a table) it's best to mount vertically to prevent accumulation of air bubbles. If flat, they can accumulate in the gears inside the sensor and affect low-flow readings.
What units does Optio Fuel work with? Can I use Metric, Imperial or ??
The Settings tab for Optio Fuel allows the use of both Imperial and Metric units. The units can be changed instantaneously in the App so users can switch between units on the fly if they want to compare. The units used are:
Volume - US Gallons and Litres
Distance - Nautical Miles, Statute Miles and Kilometres
Speed - Knots, MPH, KPH
See the Screenshot of the Settings tab below:
Do I need cellular data to use Optio Fuel? What if I'm out of range?
No, the App does not use cellular data and it will work even if you are in the middle of the ocean with no signal, but it does need a GPS enabled device (see below).
Will the maps work where I live?
Yes, the mobile apps use native maps (Apple Maps on iOS and Google Maps on Android) so the map on the App works wherever they do, which is pretty much everywhere.
We don't use any special mapping product and have customers all over the world.
I have an iPad with only Wifi, no 3G - will Optio Fuel work?
The Wifi-only iPads have no GPS in them so the speed, range and map functions will NOT work on these devices. Although the App does not need a data connection (see above) it DOES need the GPS.
All iPhones and most Smartphones have GPS built in, but some iPads and Tablets do not so ensure yours does before using with Optio Fuel.
The Fuel Flow and Totalizer will still work, even with a non-GPS enabled device however so you can use it, just not with maps, speed, optimal and range.
What GPS does Optio Fuel use?
The App uses the device's built-in GPS.
It does not need to interface to another plotter, GPS, etc. and it does not need a data connection. See more in the questions below.
Does Optio Fuel interface with NMEA or other electronics?
No, not yet. Optio Fuel and the Interactio Smart Boat app run standalone.
Where can I find the App? I searched and didn't find it...
On the Apple iOS store search for "Interactio Smart Boat" and you should find it right away. There is another company called Interactio that have an app and sometimes it gets confused.
We are currently (Jan 2018) updating the Android app so it is not available on the Google Play store until we finish and out it back up. We expect it in early 2018.
Does Optio Fuel run on iOS and Android?
Yes, we have an app for both. Search "Interactio Smart Boat" on either the Apple App store or the Google Play Store.
Can Optio Fuel handle Twin engines? Both Gas and Diesel?
Yes, no problem.
For twin gas you will need one sensor in the supply line of each engine.
If you have twin HPDI gas engines (with fuel return lines) you will need 2 sensors per engine, one in the supply and one in the return.
If you have twin Diesel engines (with fuel return lines) you will need 2 sensors per engine, one in the supply and one in the return.
When you set up the app you name the sensors from a list. The return sensors automatically get subtracted from the supplies (both flow and totalizers).
Is it possible to install a 90 or 45 degree angled fitting on the fuel flow sensor instead of straight barbs?
Yes. The connections to the sensor are standard #4 ORB hydraulic port fittings. We went with these because they are o-ring sealed and very safe. You can buy standard fittings for these or the ones we sell. Each optio fuel kit comes with a pair of barbs in the size you specify, but if you want additional fittings you can get them.
We also make an NPT adapter that adapts the ports to ½ Female NPT. It is available on the Shop page of our website.
Is the sensor waterproof and to what standard?
Yes, it has an o-ring sealed top and through-holes for mounting that come with stainless-steel screws and sealing washers that are rubber backed. When mounted properly using these screws and washers it is waterproof.
If mounting without using the screws and sealing washers, we recommend sealing the through holes with silicone or Sicaflex. It is not certified to a particular standard however.
Is the flowmeter direction sensitive or can I plumb in and out either way?
Either way, there is no dedicated Input and Output so it can be plumbed left-to-right or right-to-left (or up & down)
Can I plumb it with the hoses vertical (running up and down), or do they have to be horizontal?
Yes, you can plumb the sensor with the hoses running up and down, vertically.
What happens to the fuel use and totalizer figures when the boat is run without the display device present?
The sensor maintains the total and when you come back to the boat and the app re-connects it immediately updates the totalizer.
Does Optio Fuel restrict the fuel flow to my engine and if so, how much?
The short answer is yes, anything you place in a fluid line will create a restriction. The longer answer is it’s much more complicated. In fluid dynamics, it’s not a restriction that is the concern but the pressure drop. It all comes down to how long the restriction is.
In theory, you could force any amount of fluid through almost any size opening with enough pressure. The limiting factor for fuel supply to most marine engines is that the sensors are installed on the suction side of the pump, not on the pressure side so there is a limit to how much pressure is in the supply line.
When you compress a fluid by pushing (or pulling) it through a smaller orifice the speed of the fluid increases through the length of the orifice/reduction. In the case of Optio Fuel, the length of the restriction is mainly through the body of the sensor. When the fluid exits the restriction, it slows back down again and continues on its way. The real issue is how long the restriction is because pressure drop is exponential to the length of the restriction. If the restriction was many feet long the pressure drop would be great, but in our case it is only about 2.25 inches. When designing the sensors we intentionally reduced the diameter of the ports for our horsepower range (100-400HP) to increase the speed the of the fuel to increase gear RPM since at very low flows they spin very, very slowly.
For example, when observing the flow through a ⅜” fuel line at 1.0 GPH, the fluid exits the hose at a drip-drip-drip rate, very slowly. At these low flows the gears don’t turn and the flow does not register, hence the low end of our operating range is 1.0 GPH because below that there is not enough flow or pressure to overcome the inertia of the gears sitting in the fluid. This is not an issue on most diesels because they flow more than they consume and return what they don’t use. For inboard/outboard engines with stern drives they tend to be in the larger displacement range so flow more than 1 GPH at idle.
However, many outboard engines do not flow more than 1 GPH at idle. At idle, the Interactio Smart Boat app may show 0.0 GPH flow for these engines until the flow increases at which point it will register and display flow. If the engine returns to idle, often the flow will drop back to 0.0 again. This phenomenon can be adjusted for by using the sensitivity slider in the app to apply a rolling average to these readings from 1 to 40 seconds. This averages the flows and creates a steady averaged reading.
Regarding fuel restriction, the important factor is not so much the size of the fuel line but the pressure drop. The pressure drop is the pressure through the sensor compared to what it would be if the sensor was not there. In the case of Optio Fuel, the pressure drop is approximately 1.0 psi, depending of course on the particulars of the installation: what engines, how they are plumbed, size and location of lines, tanks, etc. As a data point we have tested Optio Fuel sensors at over 140 GPH and they run fine, you just need a big enough pump!
So in summary yes there is a pressure drop and it’s about 1 psi, which is similar to that of a new inline filter and is not significant for most marine engine fuel systems.
What is the flow range for Optio Fuel?
Optio Fuel is certfied for floiws ranging from 1.0 - 50.0 Gallons per Hour or 4.0 - 200.0 LPH.
The range of engines is approximately 100 - 400 HP, but depends on your engine's fuel flow. Note this os total fuel flow, not consumption! If your engine has a retiurn line it often flows much more fule than it consumes.
For why the range starts at 1.0 not 0 GPH see the question "Why does Optio Fuel's flow range start from 1 GPH not 0?"
Why does Optio Fuel's flow range start from 1.0 GPH (4 LPH) not 0?
For 2 reasons.
The first is safety: the sensors are designed to bypass fuel at low flows as a safety measure. In the event the gears insode the sensor get jammed by debris, a small amount of fuel will "leak" around the gears allowing the engine to still run so you don't get stranded. There is a carefully controlled tolerance between the gears and the pocket they run in. The gears teeth do not actually touch the sides, top or bottom of the pocket. This means that at low flows fuel can leak past. This is by design so that ir if the gears jam the sensor will not prevent your engine from running.
The second reason is to keep the pressure drop low so they do not restrict fuel flow to the engine. The gears are designed to NOT touch the inside of the pocket, on either side or top and bottom to eliminate frictional losses to keep the restriction low. At higher flows, the gears spin faster and "leak" very little since the fuel will take the path of least resistance which at higher flows is through the gears, not around them.
Please bear in mind Optio Fuel is not a medical or laboratory instrument and it's accuracy is dependent on your application, fuel hose sizes and engine characteristics.
How accurate is Optio Fuel?
The accuracy can vary depending on the tolerances in the sensor, the application, where it is installed and several other factors.
The gears inside the sensor do not touch the sides of the pockets by design. At flows below 1.0 GPH (4 LPH) the sensors often do not sense flow. At these low flows, there is not enough pressure to ovewrcome the inertia of the gears in the fluid. The sensors are designed to leak a small amount of fuel past the gears as a safety precaution so that in the event the gears get jammed by debris there is a built-in bypass. This is a failsafe that will ensure you can always get home and flow to your engine will not be completely stopped even if the sensor gets jammed.
The design of the sensors has been calibrated and tested against known values and in most cases are accurate to within +/- 5%.
Optio Fuel is not a medical or laboratory instrument so understanding it's characteristics is important. There is the possibility for dimensional variances that can decrease the accuracy, especially at lower flows, however the impact is often negligible considering the overall flow ranges.
What is the Warranty?
Interactio warrants the Optio Fuel flow sensor to be free from defects in materials and workmanship for one (1) year from the date of original purchase. Interactio Warranties are non-transferable and are applicable to the original purchaser only.
See the complete Warrany and Refund policies here:
What is the Bluetooth range and how far will it reach on my boat?
When you build a bluetooth product you can choose Type I, II or III bluetooth. Type I is the lowest power usage and subsequently the lowest range. This is what you get in wearables, etc. Type II is medium range, more power use but still low energy and Type III is longest range but highest power use/shortest life.
Optio Fuel is Type II which has an effective range of approx. 100 feet. Aluminum tanks, frames and other factors such as foil lined sound insulation can have an effect, but we have numerous customers with many configurations who have no issues with signal strength in boats ranging up to 60 feet. We have never had anyone return a sensor because of the range of bluetooth or low signal strength.