Trailer Modifications

The water level sensors in my RV's waste tanks simply don't work that well... It's possible that this is how it must be for exposed metal sensors, and I must simply live with it. Most of the time the tank reads full. I can only assume that the cause is the build-up of conductive waste material on the tank walls, and as long as this layer is even slightly damp, all the sensors are effectively shorted.

The RV forums are full of sensor cleaning remedies - from commercial products to driving with bags of ice cubes in the tank. Spray cleaning tools also abound, and while I am not in the mood to cut a huge hole in the tank to install a permanently mounted (and complex) spray system, I think there is something I can do about this. But first, I'd need to get in there!

Thus, the first order of business was finding the entry point - and it presented itself readily enough, in the form of a mechanical vent under the sink. The pipe leading to this device is entirely straight, as vents tend to be. Removing the vent allows me to insert something down the pipe directly into the tank, but what would that be? There isn't much clearance and thus I can't get my Camco rinser (40103) in there. So it needs to be flexible.



As it turns out, making one with parts I had on hand isn't so hard - a piece of garden hose, a barbed adapter to fit it, and a PVC cap that I blessed with a few small holes. And oh, it works.

PS: In the long run, I decided that I don't really care. I know how much water I had in the fresh tank, therefore I know how much water might be in the grey tank. And besides, it backs up into the shower when over-capacity

In an attempt to make our battery last longer on dry-camping expeditions, I measured all the electrical loads we have and found that the biggest appliance we have is the lighting system - and the Sunline has 15 interior light bulbs, not to mention outside lights all over the place. All the bulbs are 921 (spade type) and at 12-13v they consume at least 1.3A each. That's easily 18 watts. That's each! If we have, say, 4 of them turned on, that's over 5A - over 100Ah in a 24 hour period! How big is your battery?

So that was no good. There are two alternatives - compact fluorescents and LED's. I've tried LED's before, but the color temperature was horrible - very cold and white, bluish almost. They are very efficient though. As for CFL's, the idea of running something that will only glow at several hundred volts from a 12V system just doesn't sound efficient to me, so I looked into what's been happening with LED's these days. I was pleasantly surprised...

Problem: the water pump pulses on-and-off to maintain water pressure. It does a decent job, but it's noisy and the water flow varies every second or two.

Solution: install an expansion (accumulator) tank that will accumulate pressure and reduce the need for the pump to cycle or even turn on.

After some preliminary research, I ordered the parts and installed it in 2 hours (including some performance testing). Here is the how-to, largely for me to remember how I did it.

We have yet to take our first trip, but I couldn't wait. Actually I found used panels and a charge controller on Craigslist and picked them up the same day we got the trailer! Someone was selling a pair of 50 watt panels and a 15 Amp charge controller.

As it turned out, the hard part of this installation was not electrical but rather mechanical - finding beams to screw into, without perforating the rubber roof unnecessarily or causing leaks.

Some details on both electrical and mechanical install: