Most of the RVs on the road today tell you everything you need to know about liquid, battery and power levels with the RV’s onboard sensors. The one thing that is most commonly missing is how much propane you have left in your tanks.
This is an important “need to know” item, especially if you’re camping in cold weather. What would you do if you ran out of propane in the middle of the night and your family had no heat to keep warm?
With this simple solution, you will always know when your primary tank is out of fuel and you are running on your secondary or reserve tank.
My fifth wheel has two 30-pound LP tanks. I know exactly when I need to refill the primary tank because an amber warning light that comes on and I automatically switch over to the second tank.
But, in order to accomplish this modification, your RV needs to be equipped with a Marshall 250 Series two-stage LP regulator or similar model. The Marshall device, which I use, can be difficult to find. So, Camco makes a similar regulator that you can find by clicking here.
As you can see, the regulator has a “red” indicator on the top with a black cap on it. You will also notice that the regulator has a three-position lever. The straight up and down position turns the propane gas flow “off” and the left and right positions is the tank selector.
When setting the regulator flow position lever for this modification, make sure you point it to what you are going to use as the primary tank. Once the switch over takes place, it will automatically change the flow of fuel to your second tank.
To install this change over indicator, you will need to run the supplied 25-foot wire from the place where you plan on mounting the box to the LP regulator. I recommend mounting the box next to the controls for your air conditioner or heater or next to the RV tank monitor panels.
You can then drill a small hole in your wall and fish the wire down to your propane regulator. Be sure when fishing the wire, you do not catch or pull any other wires in the wall. Take your time and move the fish slow through the wall.
To hang the wire to the RV, you can use wire ties. Be sure to stay away from the electric break lines and fuel lines. You don’t want to wire tie to those due to possible pinching or splicing into the wires.
One you have the wires run, mount the LED and battery box to the location on the RV wall you have selected with the supplied self-tapping screws. Install the two AA batteries into the battery box. At this point you can connect the regulator indicator plug to the regulator.
Remove the “black” cap on the top of the regulator. You will just pull gently on the cap and it will pop right off. Using the new regulator cap, gently push it onto the regulator making sure that the pin in the middle of the cap is going into the hole that you exposed when you removed the original cap.
Using the two wire nuts that were supplied, twist the wires together. There is no color coordination or right or wrong.
Testing the new LED change over indicator
Turn on both LP fuel tanks and make sure the tank selector is pointing to the primary tank. Now, turn off the primary tank only and you should see the amber LED light turns on. If you start your stove or LP hot water heater, you should still get a flame on both devices.
Then turn the primary tank back on and the LED light should go off.
Now you never have to worry about running out of LP gas. As soon as the amber light goes on, you know you’ll need to fill the “primary” tank soon.