Fitting a Water Tank and Float Switches


TOTAL: £174.20

You can see a diagram of my full water system here.

Like a lot of van builders, I decided to opt for a 70L Fiamma water tank for the van. I then decided to use a pair of float switches wired to some indicator lights so I can see how full the tank is without having to open the back doors. Float switches simply cut power to the circuit when they aren’t submerged in water, so if you have one connected to a light, when the light goes out, you know that the water level is lower than the switch.

Fitting the Water Tank

I decided to put my water tank in the rear corner of the van, as it fitted nice and snug below my bed up against the wall. I happened to have some spare 9mm plywood lying around, so I cut two pieces that I could use to cover the water tank and hold it in place. 

The first step for the tank was to drill some holes for the water inlet, water outlet and also for the two float switches. The water tank comes with a little water outlet fitting, so I drilled a hole in the bottom of the tank and screwed that in place. 

I then drilled two more holes roughly a third and two thirds up the spine of the tank for the float switches. I then screwed them in place the same way as the outlet. 

Lastly, in the top of the tank there were two holes to be drilled, one for the main inlet and one smaller hole to relieve air pressure in the tank.

Once the holes were drilled and all outlets and switches firmly in place, I positioned the tank under the bed and then screwed the section of ply facing the rear of the van into the floor and the bed above. This part of ply had a small section cut out in order to house the inlet. Before screwing it in place, I cut two small lengths of 38mm hose and 12mm hose, connected one end to the tank and then the other two the water inlet, fixing them tightly with jubilee clips. I then screwed the water inlet in place. 

The last step was to screw the other section of ply in position.

Connecting to the water pump

I cut a small section of 12mm hose that would fit between the water outlet of the water tank and the water pump but before fixing this in place, I cut the section of hose in half and fitted a ball lever valve. I did this in case I need to shut off water from the tank and isolate the pump and accumulator. 

I fastened the sections together with jubilee clips. 

Wiring the float switches

Because I had two switches and two lights, I connected them in parallel so that I could connect them to one point on the 12V fuse box. 

I used a hoop connector to connect some red wire to the fuse box and then a male and female connector to connect the other end to the positive wire of the light. I again used a male and female connector to connect some black wire to the negative wire of the light and then connected that to one of the wires of the switch. I lastly connected the switch to the negative terminal of the fuse box to complete the circuit.

To wire the other switch/light in parallel, I used a T-connector to intersect the wire between the fuse box and the first switch and then connected the positive wire of the second light to the T-Connector. 

I used some black wire to connect the light to the other switch and then again used another T-connector to connect the switch to the negative wire connected to the fusebox. 

If you have any questions at all, feel free to ping me an email or drop me a message on Instagram!