The air suction is part of the automatic milk frother. It regulates air flow into the milk resulting in fine milk foam. The air suction will need to be replaced periodically. Every 9 - 12 months is typical. A blocked air suction will result in milk that is flatter (less air) and cooler.
We were unable to bring your accounts across to the new website. Please re-register your details. If you have a business credit account with us you can select 'My Coffee Shop Account' at checkout. We apologise for the inconvenience and thank you for continued support! Regards the MCS Team.