Printing apparatus on a print support comprising: - A print head to print on said print support a print material; - A feed device to feed said print material to said print head , and - A recirculating unit to generate a recirculation of said print material through said print head , said recirculating unit in its turn comprising: a. A first container of said print material placed upstream of said print head ; b. A second container of said print material, placed downstream of said print head ; c. A first recirculating sub-unit to generate a first flow of said print material from said first container to said print head and said second container ; d. A second recirculating sub-unit to transfer said print material from said second container to said first container , wherein said first container and second container are both maintained under two distinct negative pressures and in which the feed device comprises an accumulation tank , a pumping device and an ink refilling pipe for feeding refilling ink to a first container of the recirculating unit , which ink refilling pipe connects the output of pumping device with the said first container , and a pumping device control unit is provided; characterized in that the pumping device control unit is configured to drive the pumping device in a pulsed manner, for feeding in an alternate manner predetermined amounts of ink from the accumulation tank to the first container. - A print head to print on said print support a print material; - A feed device to feed said print material to said print head , and - A recirculating unit to generate a recirculation of said print material through said print head , said recirculating unit in its turn comprising: a. A first container of said print material placed upstream of said print head ; b. A second container of said print material, placed downstream of said print head ; c. A first recirculating sub-unit to generate a first flow of said print material from said first container to said print head and said second container ; d. A second recirculating sub-unit to transfer said print material from said second container to said first container , a. A first container of said print material placed upstream of said print head ; b. A second container of said print material, placed downstream of said print head ; c. A first recirculating sub-unit to generate a first flow of said print material from said first container to said print head and said second container ; d. A second recirculating sub-unit to transfer said print material from said second container to said first container , wherein said first container and second container are both maintained under two distinct negative pressures and in which the feed device comprises an accumulation tank , a pumping device and an ink refilling pipe for feeding refilling ink to a first container of the recirculating unit , which ink refilling pipe connects the output of pumping device with the said first container , and a pumping device control unit is provided; characterized in that the pumping device control unit is configured to drive the pumping device in a pulsed manner, for feeding in an alternate manner predetermined amounts of ink from the accumulation tank to the first container. <EOS>