vauxhall zafira 2.0DI - idle speed - teebird69

Hi, was wondering if anybody knew what the correct idle rpm for this car was, as mine from cold is the same all the time 1100rpm. I thought that this was a bit to high as other diesels i have owned all seem to idle at about 800 / 900rpm when the engine has warmed up... I changed the thermostat as this had been suggested as it might of been interfering with the temperature sensor but still remains the same.... any suggestions please......