Heater

My 07 plate Roomster 2 has developed a fault with the heater, the control doesn't seem to have any graduations, its either hot or cold with nothing in between. Any ideas folks? Also, my digital instrument pod was replaced a year ago but I couldn't find my spare key, the dealership has closed and now I'm left with a key that requires coding, any alternative to dealership rip off prices ?

Edited 4 October, 201511 yr by denkirk