RV Converter Fan Keeps Running: The Best Answer On Why

 Your RV Converter is a critical power source for your home on wheels. Even when connected to shore power, the converter works hard to convert that AC current into DC power.

As it works hard to convert AC power to battery power, it will generate heat. And luckily, that heat doesn’t cause damage to the converter since there is a fan to expel it.

But should that fan keep running? What is the problem, and how can it be fixed if not?

The most common reason an RV converter fan keeps running is low battery voltage or poor ventilation. This post will review each cause and the solution, including

  • Converter Fan Function
  • Battery Charge
  • Battery Voltage
  • Poor Ventilation

 I must pause here and make a quick distinction that is a common mistake. An “Inverter” is different than a “Converter.” An “Inverter” takes DC power (from a battery) and converts it to AC output, such as household appliances. Whereas a “Converter” converts AC Power to DC Power. Think of a “converter” more like just a battery charger.

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All modern travel trailers and RVs have a converter since most safety devices and pumps work on DC power. Visit my post for a complete list of what runs off a battery in your travel trailer.

Converter Fan

Do you constantly hear that fan noise coming from the converter? You are correct if you suspect that the fan motor should not run all the time!

The converter uses this cooling fan to expel the heat generated by converting the AC shore power into battery DC power. Usually, when the system operates as it should, the fan motor turns on at a certain temperature and then turns off once those fan blades have cooled down the converter.

But, there are times when the cooling fan can’t keep up with the heat generated by the converter, and it will keep running. Let’s explore what can cause this constant heat.  

RV Battery

The converter’s main function is to charge your RV battery and keep the voltage above 12 volts. As the converter works or charges the battery, it usually has no issue keeping up with the demand, and the heat generated can be removed by the cooling fan.

However, if there is an issue with the RV battery and the converter is constantly running to keep the battery charged, a lot of heat will be generated. And with that heat, the converter fan will stay on as it works to top off that battery.

If there is not much battery life left or it cannot hold a charge, the converter will work extra hard and generate extra heat to keep up with the demand of the RV.


Check your RV battery. Look for signs that could affect its ability to hold a charge. Check the battery terminal and the battery cable for a clean connection and good metal-to-metal connections. Any signs of corrosion or loose connection can cause the battery not to charge properly and the converter to work extra hard.

Another check is the circuit board. Make sure you don’t have a blown fuse or a tripped breaker. If a blown fuse or circuit breaker disconnects the battery power, the converter will continue to run and try to provide power without the battery. More info on your converter running without a battery.

Battery Voltage

Another cause of your battery could be low voltage. If it reaches the end of its battery life, it’s hard for a deep-cycle battery to retain voltage. Depending on the appliance wattage demand from your RV, the battery voltage may be unable to keep up.


Check your deep cycle battery with a multimeter. You should have anywhere from 12 volts to 13.3 volts. If your battery is at or below 12 volts, it is likely past its battery life and needs to be either fully charged before use or should be replaced. A deep cycle acid flooded battery lasts around 3 – 5 years, with an AGM at 5 – 7 years. If you are approaching those dates, it would be time to look into a new battery.

Poor Ventilation

Poor ventilation and the fan’s inability to get the heat out is another possible cause. Besides the fan running, it is important to have ventilation so that hot air has a place to go. Any blockage in the ventilation will cause the fan to be inefficient and keep running.

Keep the area clear in front of the converter for fan ventilation

Always keep the area in front of your converter free and well-ventilated. It’s no coincidence that converters are in the open with good ventilation.


Check around your converter to ensure that the area is free and clear. Any blockage of the converter fan will cause the heat not to escape and the fan to constantly run.

Final Thoughts

When your RV converter fan keeps running, it works extra hard to meet the appliance demand. A weak battery causes the converter to work harder, while poor ventilation prevents heat from escaping. Both cases keep the fan running to try and achieve proper operating temperature.