Waste tank - half full or half empty?

[Archiesgrandad]

My experience is that the fresh water tank will have a device the allow some rough indication of the contents, and it will be more or less reliable because it operates in clean water. The grey water tank will have a much cruder device which will only indicate when the tank is more or less full, because anything more sophisticated will only get clogged up with the gunge. On our Rimor there were two 2" self tappers screwed through the tank top with wires attached, when the fluid touched the screws the light came on.

AGD

[bolero boy]

Derek Uzzell - 2013-01-11 6:42 PM

 

The Truma C-3402 appliance retro-fitted to my Herald began to leak water. As with bolero boy's Combi heater, a tiny flaw in the stainless-steel tank was causing the problem. I asked the Truma technicians at the time whether adding Milton to the fresh-water might have provoked the flaw, but they dismissed that possibility, concluding that the 'pin hole' (which was on a weld line) was due to faulty manufacture.

I suspect our issue was the same, Derek, a flaw in a weld line. Truma just chose not to give us any more detail other than to tell us it would be replaced.

[Derek Uzzell]

There are systems with the potential to provide accurate readings of contents-levels in leisure-vehicle reservoirs and not be affected by contamination. There's a useful article on RV tank gauges here:

 

http://www.andybaird.com/travels/skylarking/improvements/gauges.htm

 

Many European-built motorhomes have a fresh-water tank probe-type sensor system of the type shown here:

 

http://www.rvsupplies.co.nz/files/product_attachments/957/RVL540.pdf

 

Even if the lengths of a probe's stainless-steel rods are appropriate for the depth of the reservoir and the rods are perfectly clean, 'tilt' may still need to be taken into account. The probe for my Hobby's roughly cube-shaped fresh-water tank is positioned towards the rear of the tank. If the motorhome is parked level the contents-readouts are consistent. However, if the vehicle is parked nose-up the gauge will be over-read and, if the vehicle is nose down, the gauge will under-read.