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What does DSI FLT mean on an RV? (Explained)

What does DSI FLT mean on an RV? (Explained)

Hot water is an essential part of living, even when you are traveling on the road in your RV. Unfortunately, hot water heaters act up at times, making it difficult to get that hot water you need.

The good news is that RVs come with system codes that can help you pinpoint the exact issue. One common code is DSI Flt.

What does DSI Flt mean on an RV, though?

DSI Flt means that there is a direct spark ignition (DSI) fault (Flt). The direct spark ignition is responsible for causing the flame in your gas heater, which keeps the water hot. Whenever you see this code, there is likely no gas coming through your water heater line.

Knowing what DSI Flt means is only half the battle. You also have to know how to practically fix the problem to get your hot water working again. Scroll down to learn more about the meaning behind DSI Flt and what you should do about it.

Definition of “DSI Flt” on an RV

Anytime you see an Flt code ring up on your RV, it means that there is some kind of flaw or fault that needs to be adjusted. The code that comes before Flt is what tells you what exactly is wrong with your RV.

In the case of DSI Flt, it means that there is a fault in your direct spark ignition.

The direct spark ignition automatically lights the gas in the water heater once the power switch is flipped on. This system is much safer than older methods because the gas supply will automatically lock if it fails to light the gas three times.

Additionally, the Control Board will turn off the water heater’s ignition if a specific temperature is exceeded.

Both of these automatic control features how to keep your RV safe, but they can also trigger a DSI Flt. As a result, your water will not be heated, and you will have to fix the problem. The good news is that the problem is super easy to fix.


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How Do I Fix DSI Flt on RV?

If you see a DSI Flt on your RV, it means that no gas is coming through the line, most likely due to automatic safety control. In order to get this feature to go away, you will have to reset the water heater. Although this sounds difficult, it is very easy to do.

For most modern RVs, the water heater will come with an automatic reset button. Just by hitting this button, you will reset the water heater, and the DSI Flt will be fixed. Here is a closer look at how to fix the problem.

1. Locate the Reset Button

The first step in fixing a DSI Flt is to locate the reset button on your water heater. This button is typically found on the outside of your RV, right on the WH panel. In most panels, the button is right on the left side once the panel is opened.

That being said, the reset button can be placed in other locations. If you cannot locate the reset button, look at your user control manual. All buttons should be clearly labeled so you can determine where the reset button is located.

2. Press the Reset Button

After you find the reset button, all you need to do is press the button. Upon pressing the button, the component will be reset. You will have to wait for the water heater to effectively heat up all the hot water, which will take a bit.

3. Wait for the Clicking Noises

To ensure that the DSI is working again, you must wait until the DSI finishes its three lighting attempts. You will hear clicking noises whenever the DSI does this.

What If I Still Run Into Problems?

In most cases, a DSI Flt is fixed with the steps above. Occasionally, your system may work at first but eventually fail in just a short amount of time.

Whenever this happens, other parts of your water heater are probably not working correctly. You will need to test different sections of the water heater to pinpoint the exact issue.

In most cases where resetting the water heater does not fix the problem, there’s likely an issue with the supply valve. Replacing the supply valve will fix the problem.

How to Prevent this from Happening in the Future

There’s very little you can do to prevent the DSI Flt light from coming on, especially when it comes on due to safety reasons.

For the most part, maintaining your water heater appropriately will help to minimize Flt lights from coming on at all. At least once a year, make sure to perform visual inspections of the water heater. Make sure there is no rust or obvious signs of damage.

Perform a water tank drain and flush any time the RV is not being used. Doing so will extend the anode rod life and keep the overall water heater healthy.

Once it’s time to hit the road again, fill the water heater and inspect it to ensure it is working correctly.


Final Thoughts

If you see a DSI Flt code, it means there is a fault in the direct spark ignition. Although this may sound like a big problem, it normally occurs just because the system shuts down for safety reasons.

Although there are other potential causes for a DSI Flt code, most of them just require a quick reset.

As such, the first thing you should do any time you see a DSI fault code is reset the water heater. Most of the time, this will fix the problem, and it only takes a couple of seconds to fix without any additional money.

If the problem is not fixed after resetting the water heater, there is likely something bigger to blame. In this case, you’ll probably need to replace the supply valve, but make sure to inspect the entire water heater so you can target the exact problem plaguing your RV.


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