Air condition Ford Galaxy?

We bought Galaxy reg 08, in winter, we use fan and everything was ok, until we realise air con wasn't warking, so ford garage repaired it, they replaced some pipes, but the problem just occur, we replace also pollen filter, and antibacterial treatment was done on it, when air con is on, there is little bit of smell, but as soon as we turn off air con, the smell is disgusting, so I don't know what to do whit that, I am going to tell ford garage to replace whole aircon because it's like that for a month. Anybody had problem like this?