You will find out that the circulation pump will not switch on and the green and amber light are both illuminated.
Remove the unions from the waste valve and check for any blockages.
Check the fuse inside the control box. This is located in the hinged compartment on the left hand side of the pump connector block. The fuse is a standard 10 Amp glass fuse.
If this does not solve the problem, contact your Evolution Aqua dealer.