I have a Testo 330-1 that seems to eat CO sensor cells. Anyone have similar problems. The highest reading the last cell encountered was 3100 ppm. A high CO warning alarmed and it was removed immediately. After that, the CO would not work until a new cell was installed. They're supposed to be good for 5000 ppm. The first cell replacement came after about 0.9 hours of use according to the isntrument's recall. That's not much time of general exposure in my opinion and the instrument wasn't exposed to high ppm readings whatsoever that time. Testo isn't any help, except to advise me to 'order a new cell'. It just seems to me that 0.9 hrs isn't much exposure and a one time hit of 3100 ppm shouldn't kill a sensor cell. Any advice? At $230/sensor and a sensor every couple of months (I'm not even using it that often) this thing needs to be tossed so I can cut my losses.