One of the most common questions RVers ask is how to keep their fridge running efficiently while on the road without relying on propane. In this blog, we’ll explore this exact topic, using insights from a recent video where Todd tackled a question from RVing with Bandit. Here's what we learned.
The Question:
RVing with Bandit wanted to know how to keep their RV fridge running without propane during long drives. They mentioned having a 1,200-watt inverter, a 280-amp-hour lithium battery, and a 30-amp DC-to-DC charger from the coach alternator. The challenge? Making sure the inverter could power the fridge without draining the battery over a 6- to 10-hour drive.
Is It Safe to Run the Fridge on an Inverter?
First, it’s absolutely safe to run your fridge off an inverter. This is what inverters are designed to do—convert your DC power into AC power to run your appliances. Many OEMs set up smaller inverters to power essential circuits like kitchen outlets and the refrigerator. So, if your inverter isn't currently powering the fridge, it might require a qualified technician to rewire your system.
Will the Battery Last for the Entire Drive?
This is where math comes in. With a 280-amp-hour battery, let’s assume you can safely use 250 amp-hours. Multiply that by 12 volts, and you get roughly 3,000 watt-hours of energy available from the battery.
Now, your fridge will likely consume between 300 and 500 watts per hour depending on its size and efficiency. Using the higher number to be safe, let’s assume it uses 500 watts per hour. If we divide the 3,000 watt-hours available by 500, you get approximately 6 hours of runtime.
But you’re not relying solely on the battery. Your DC-to-DC charger is also feeding power from the alternator while you drive, which can provide an additional 350 watts. This should allow you to stretch that runtime closer to 6-10 hours, depending on factors like how much power your alternator is outputting and what other appliances you have running.
Additional Tips to Prolong Fridge Runtime
- Pre-Cool the Fridge: If your fridge is already cold and stocked with cold or frozen items, it won’t have to work as hard.
- Frozen Food as a Cooling Buffer: Place frozen items, like a pound of beef, in the fridge to help maintain the temperature for longer periods. Heat moves from warmer to colder objects, so this trick can reduce how often your fridge’s compressor kicks on.
- Avoid Opening the Fridge Frequently: Every time you open the door, cold air escapes, and the compressor has to work harder to restore the temperature.
The Verdict: Can You Do It?
Yes, you can power your fridge with your inverter while driving without needing to run your generator. Just make sure everything is wired correctly, and be mindful of your battery consumption, especially on longer drives.
Have more questions or want to dive deeper into RV tech tips? Drop your comments below, and we’ll keep the tech advice rolling!