Turn the blue knob anti-clockwise until you hear water flowing in. The pressure on the manometer should be about 1.5 bar, tighten the choke. Continue looking for moisture in the installation. Check the screw connections and the breather. Below 1 bar, do not use a junker because you will stop the pump and it costs about PLN 1000. The boiler is not protected against water loss, so you need to take care not to damage the device.
