A pressure controlling system for an inkjet printer, the system comprising: a pressure chamber having a volume; a pump fluidically connected to said pressure chamber and adapted for increasing the pressure within said pressure chamber by pumping air into said pressure chamber and for decreasing the pressure within said pressure chamber by pumping air out of said pressure chamber characterised in that the pressure control system further comprises: a controllable three port two way valve (4, 104) having a first port controllably fluidically connectable to said pressure chamber, a second port controllably fluidically connectable to one or more inkjet print heads and a third port controllably fluidically connectable with atmospheric air; and a pressure sensor unit comprising one or more pressure sensors, said pressure sensor unit is in fluidic communication with said pressure chamber for sensing the pressure within said pressure chamber; wherein said pressure sensor unit is adapted for sending signals representative of the pressure within said pressure chamber to at least one processor/controller, and wherein said pump is adapted to receive control signals from said at least one processor/controller for controlling the operation of said pump and said valve is adapted for receiving control signals from said at least one processor/controller for controlling the operation of said valve. a pressure chamber having a volume; a pump fluidically connected to said pressure chamber and adapted for increasing the pressure within said pressure chamber by pumping air into said pressure chamber and for decreasing the pressure within said pressure chamber by pumping air out of said pressure chamber characterised in that the pressure control system further comprises: a controllable three port two way valve (4, 104) having a first port controllably fluidically connectable to said pressure chamber, a second port controllably fluidically connectable to one or more inkjet print heads and a third port controllably fluidically connectable with atmospheric air; and a pressure sensor unit comprising one or more pressure sensors, said pressure sensor unit is in fluidic communication with said pressure chamber for sensing the pressure within said pressure chamber; wherein said pressure sensor unit is adapted for sending signals representative of the pressure within said pressure chamber to at least one processor/controller, and wherein said pump is adapted to receive control signals from said at least one processor/controller for controlling the operation of said pump and said valve is adapted for receiving control signals from said at least one processor/controller for controlling the operation of said valve. a controllable three port two way valve (4, 104) having a first port controllably fluidically connectable to said pressure chamber, a second port controllably fluidically connectable to one or more inkjet print heads and a third port controllably fluidically connectable with atmospheric air; and a pressure sensor unit comprising one or more pressure sensors, said pressure sensor unit is in fluidic communication with said pressure chamber for sensing the pressure within said pressure chamber; wherein said pressure sensor unit is adapted for sending signals representative of the pressure within said pressure chamber to at least one processor/controller, and wherein said pump is adapted to receive control signals from said at least one processor/controller for controlling the operation of said pump and said valve is adapted for receiving control signals from said at least one processor/controller for controlling the operation of said valve.