2006 LR3. It has a refrigerant leak I haven't fixed so I haven't had A/C for a year. But last winter the heat gave out on the drivers side. The passenger side worked fine but couldn't keep up when competing with ice cold driver side.

Any ideas?

 

I don't own an LR3 but I've had this issue with other vehicles and it's caused by a failed blend motor. The system uses flaps to adjust the air flow to each side. If it stops working, then it will direct outside air into the cabin instead of the warm air from the heater core.