I read a lot of customer recessions and thought to myself that many error descriptions (no connection to Aussensor) more errors due to the large distance or is prevented by masonry. Also, I thought ... okay..gibt sometimes Monday appliances and the large number of sales can there already something come together to bad reviews. But no, it is in fact a weakness in this model. My first instrument lost after about 3 months the connection. I changed all the batteries and put the two parts together. Half and Amazon not exchanged me easily from the device to a new one. Same error for about 1 week, and then I lost interest and sent back the unit.