AirCon making strange sound?

[drewr]

Possibly faulty fan? Jmac hinted a while ago the possibilities of a "TV valve*"? I've done extensive searching on that and have found nothing of the sort, so im thinking i may have it confused with something else?

[WhO]

"TX valve" not TV valve. It's a valve that controls the amount of refrigerant flow into the evaporator. How it'd make it hum i'm not really too sure!

Does seem odd its only when there's an element of lock :/