Refilling Harvey Water Softener

[tommyleestaples]

Hi all,

 

I have been storing my Harvey HV3 water softener for the last 6 months in my shed. I have not had a plumber refit it in kitchen cupboard and all pipework is correct. However, when we turn the water on to the softener you hear the water running but the tank does not fill up the water just comes out of the air gap fitting and down the pipe going outside. 

 

Please can someone advise how to refill, it is a case of opening the inlet first before opening the outlet or do I need to manually fill the tank up with water first as it is completely dry in there?