Asking for advice

Hi,

I am requesting advice on something that has completely perplexed us.

I have a twin immersion water heater.  The off peak element stopped working followed by the boost element.  Both elements have been tested and the off peak element has a current, and a loose wire has been fixed.  The boost element has been replaced as was dead and waiting for a new switch which will hopefully work.

Confusion lies with the off peak element, electrician felt it would work after fixing the loose wire but it hasn't.  Still getting a reading which has implied that the element is working.

Any advice on next steps would be appreciated.

Thanks

What or how did he test the element? 

Voltage tester.

Then I replaced the one that wasn't giving a reading.  

The other one showed a consistent reading (After the lose wire was fixed)

what controller do you have? i.e. what make?

Horstmann E7BX controller.

Connected as the right pic? 

http://horstmann.securemeters.com/files/7414/7011/7869/installer_instructions_E7BX.pdf

My money is on the controller has partially failed......