LMP91000: Not working properly.

Hi,I'm using the LMP91000 temperature sensor and it always gives me 900 mV as an output which would mean my room is at 80 centigrades. The configuration is the following: 0x03 for the TIACN, 0x20 for the REFCN and 0x06 for the MODECN. I'm using Arduino for communication through I2C to program it and it seems to be working fine, because when I put the deep sleep mode it gives 0 mV, so I don't know what is the problem. I have DGND, AGND, DAP and MENB to ground, VDD is 3.3 V and I have nothing on C1, C2 or VREF because I'm using the internal (I also used the external and changed the configuration and it didn't work). Also, I have a Spec Sensor connected to CE, RE and WE which doesn't seem to work properly when I configure the sensor to measure any gas. Any comments will be gratefully received. :)