When you try to select hot air from cold inside the car do you hear the air flow change?

You should hear it when it swaps over.

If not, do what adam said.

if its a corsa -b then pop the panel off and check the hot cold selector rod hasn't become unclipped from the panel

i'm having the same problem

and i've tried clearing the airlock thing...

when mine came out cold all the time was only when we changed the head gasket it changed

Think he means it's cold air coming out. Maybe you use water in your coolant and it's frozen somewhere due to cold weather?

do they come out at all?

hello i have a 1.2corsa b and the heaters arnt working , the fan is working fine and so is the far rite dial just the heat dial isn't changing the temp even wen the car is reli warm

any help

thanks