Water level sensors

fresh water tank level sensor showing full when it’s not, so not letting external pump get power, has anyone changed these sensors if so is it just a case of undoing nuts pulling sensor out, looks very like a rubber raw plug . As a temp fix can the cable o the top sensor (full) be separated as to not register on control panel allowing external pump to run

There is no connection between the level sensors and the pump operation. On the control panel you can set pump power to internal, external or both and the pump switch has to be on for any to work, best to set to both

The Whale fill system has its own float switch in the tank and if the tank is actually full it will switch off the power to the external pump.

If water tracks between the sensors on the tank (either inside or outside) or penetrates the inline connector in the wiring loom, the tank level indication will always show full.

As far as I know there is no float switch this has been an ongoing problem with the dealer who tell me it is a sensor problem , been on a campsite where did not have mains water so wanted to fill from a 40lt container this was not possible as no power to my external pump plugged in, all power at control panel on , external pump only works when not showing full, can park it up at home showing 25% water get in the morning showing full.have temp got round it by buying spare pump connect a cig plug and a length of pipe,  plug it in to external tv 12v socket. Spoke to Sargent today known problem corrosion on sensors ,did ask can I disconnect 100% sensor as a way round , told ok but not a proper fix. Has anybody tried this ? Could do myself but still has warranty. How hard can it be!! Been in the motor trade 32 yrs if only Motorhome’s and caravans were designed by the people that use them

Whats the point of asking for help if you know better anyway?

It’s not that I know better because I don’t that is why I’m asking has anybody disconnected the 100% wire , sorry if comes  across that way .

Not that easy to get to as need to disconnect water pipes could just cut wire, re- connect later but being under warranty will not be good , but do seeing it if an ongoing problem with this system so maybe later just asking has anybody done this and does it work.thankyou

Thanks for reply as said have rigged up a pump with 12v plug and hose can fill into filler this way , just think progress has gone backwards if it an’t broke don’t fix it . Back to the dealer it is then cheers. Steve

Peter Brown wrote:Whats the point of asking for help if you know better anyway?

Sorry Steve R, had a bad day yesterday but thats no excuse.

Auto-sleeper use the Whale Autofill system:




The ability for the Sargent water level sensors to switch off the external pump should not be implemented on an auto-sleeper so you may have the wrong software in your EC700.

The bottom sensor on the tank is the common one.  If any other is connected to the bottom then 25% indication, any 2 50%. any 3 75% and all 4 100%.

If the sensors have scale on them you get 0% when the tank has water in it.  For the level indicator to show 100% all 5 sensors must be connected together either by tracking across sludge in the tank (use a proprietary tank cleaning fluid), water ingress into the wiring loom, a wiring fault or an EC700 fault.

Thankyou Peter and carman have been onto dealer today they are having back to change sensors (Sod’s law at moment all working as should ) there’s always a way round it but if it should work it should. Cheers. Steve