hello dear , if you feel the air is blocking Frequently and defrosting not enough then you need to check the quality of you cooler hose and if better to replace it if found not good ,and remember that new hose for Zimmer is available in our store here in good price
I have a cryo 6 Zimmer machine and it working good most of time but sometimes I feel not good air coming
Even we make defrost it's not responding