Installing sensor in water tank

[JafaJones]

Hello fellow vanners, after years of juggling water tank level anxiety I have decided to install a gauge and sensor in my 2009 Swift Challenger. My caravan had underfloor tanks fitted by the previous owner, these are clamped up against the floor with no access unless I lower them - with associated risk to the inlet and outlet piping.
I can access the top of the tank through the floor in one of the lockers, I propose to use a hole saw to cut through the floor (ply/foam sandwich) and then through the Polyethylene plastic tank. The sensor fitting would then be screwed to the top of the tank and connected to the gauge which would be installed alongside the existing switch panel above the door.
My question(s), have any members already done this, do you have any clever suggestions esp re preventing swarf getting into the tank and then getting any that does get there out. The existing piping to the tank appears to be glued in so unscrewing is not an option to drain the tank and it does not appear that there are filters in the pump line.
Thanks so much for reading and any feedback.
Regards Mike (Auckland New Zealand)

 

[IanB1485]

To clean most messes inc swarf off my lathe I have a wet/dry Titan vacuum cleaner it's very good (hell of a suction) and when wanting to get into small places I attach a small diameter pipe to the end of the hose such as 12mm flexible pipe.

 

[Beardy]

Hello fellow vanners, after years of juggling water tank level anxiety I have decided to install a gauge and sensor in my 2009 Swift Challenger. My caravan had underfloor tanks fitted by the previous owner, these are clamped up against the floor with no access unless I lower them - with associated risk to the inlet and outlet piping.
I can access the top of the tank through the floor in one of the lockers, I propose to use a hole saw to cut through the floor (ply/foam sandwich) and then through the Polyethylene plastic tank. The sensor fitting would then be screwed to the top of the tank and connected to the gauge which would be installed alongside the existing switch panel above the door.
My question(s), have any members already done this, do you have any clever suggestions esp re preventing swarf getting into the tank and then getting any that does get there out. The existing piping to the tank appears to be glued in so unscrewing is not an option to drain the tank and it does not appear that there are filters in the pump line.
Thanks so much for reading and any feedback.
Regards Mike (Auckland New Zealand)

Could you fix (glue) 4 of these to the outside of the tank to give you full, 3/4, 1/2, 1/4 signals (and avoid drilling the tank all together)?

Pardon our interruption...

 

[JafaJones]

Hi everyone, your suggestions much appreciated and are reflected in what I have done. I have now completed the tank sensor install, a larger hole through the ply/foam/ply sandwich, drilled very carefully using a new Bosch 60mm long hole saw with frequent vacuuming to get the swarf out prior going into the tank. The tank installer had inserted a sheet of polystyrene between the tank and floor, I guess to jointly control vibration and help with any variations in the surfaces. The polystyrene helped identify when I got through the lower ply and protected the tank from the hole saw center bit.
I was able to thoroughly vacuum the floor and foam debris out then cut the polystyrene out with a stanley knife before drilling into the plastic tank with the smaller hole saw, again with several stops to clean out the swarf and then I was through - yay. The tank outlet had been glued and I have decided to cut the plastic pipe so I can rinse and swarf that got into the tank, out.

Tomorrow's job will be to install the gauge and wiring. I checked everything with a battery charger so I know it all works.

We are off for a month around the South Island at the end of Feb and fingers xxx, no more water level concerns

Thanks again for the advice and suggestions

Cheers

Mike