Bailey Unicorn 3 cordoba

Only just spotted your post.  If it's the same as our Barcelona, there is a valve under the offside front seat which has to be turned to allow the inboard tank to be filled using the external pump from the Aquaroll.  However, I assume you have tried this if you have read the manual.  We had a problem when ours was new in that the tank wasn't filling.  Took the technician at the dealer's two hours to trace the problem to a trapped pipe hidden behind the sink unit. Once he had replaced the pipe, everything was fine.

We have the Cordoba. Above is correct, but you don't necessarily need to use the aquaroll. If you are connected to mains the tank will fill when you turn the valve under the front offside bunk. Tap at 90 degrees to pipe directs supply to taps etc. Valve in line with pipe fills the tank. You have to watch under the van for the overflow to start running - that is thebonly indication you get that the tank is full.

Also make sure that all the yellow drain taps are closed - flat against the pipes.