Mod: Fresh Water Tank Gauge
DETAILS: Fresh Water Tank Gauge
One of the most challenging parts of boondocking is managing your fresh water tank levels, which is made more difficult since it’s nearly impossible to gauge how much is actually in the tank! I’ve finally solved this by creating a window with a wide-angle view, a backlight behind the tank, and a scale with precise measurements from 0 to 32 gallons.
First, to make accurate measurements, I ran my tank dry to the point when the water pump was no longer picking up any water. Even though there was still some water in the tank (approximately 1” of water), it was unusable. This level is where I marked “0” gallons left. Then, with a digital water flow meter, I added exactly 5.0 gallons of water and then stopped. I went inside and made a temporary mark on the tank with tape. I did this same thing six times, adding water in 5.0 gallon increments and marking the tank with temporary tape.
To make an accurate and legible gauge, I created a visual scale on a plexiglass sheet (purchased at Lowes) custom-cut to the dimensions 5.5” wide x 18” tall. I measured each tape mark from the floor up, and then re-created the same scale on the plexiglass with skinny black adhesive tape and black peel and stick numbers (both purchased at Michaels arts and crafts store). Note: the vertical distance between each 5 gallon increment isn’t linear since the tank is an odd shape!
The special window is part of what makes this mod work — the fresnel lens allows you to see the entire tank, top to bottom, even though you’re looking through a small hatch from a distance. I purchased a second custom-cut plexiglass sheet (9” x 9”) as well as a flexible wide angle fresnel lens (linked below) which I cut to 9” x 9” and then fused the two together with water (per the directions that came with the lens). The black border holding the two together is simply Gorilla tape. The window, which I made only as big as the opening, is then held in place with Velcro.
Last but not least — the backlight. Without it, you can’t see the tank level. Even if you shine a flashlight on the side of the tank you can see, the illumination bounces back and makes it hard to see the current water level. I used the same lighting that I used under my cabinets and slide (see LED Accent Lighting mod). To access the back of the tank on the J model, I raised up the bed from the headboard side and reached my arm down. The LED strip lights have an adhesive back and attach easily.
For power, I ran the wires under the carpeted subfloor (under the J bed), into the water heater compartment and then tapped into the positive and ground wires feeding the OEM light in the under-the-bed storage compartment. I added a switch at the foot of the bed, under the TV, next to the light switch. There was actually a dummy bezel already in place (in some J models I believe this is already a functional switch if the TV is 12v). An alternative location for a switch is under the bed since you need to tilt it up to see the tank window anyways.
Wide Angle Fresnel Lens: www.campingworld.com/wide-angle-lens-11-x-14
12v LED Strip Lights: www.amazon.com/dp/B00WQFP1LU
Wire Noodler Kit: www.amazon.com/dp/B01LXCJSRP