Prime the unit by putting the generator unit on the floor and hold the iron itself up higher. Make sure that you have the heat and steam settings on 'maximum' then keep your finger on the trigger for about 5 – 6 minutes without letting go and try shaking the wire. This will not damage the unit and we only advise our customers to do this if they have an air lock.
Whilst carrying out the above you will hear the usual pulsating noise as normal, which should go quieter as the shot of steam works its way through the unit.
You can also try to prime the unit the opposite way round by having the generator unit on a high surface holding the iron at a lower level.