CDO

Hi there! I'm a student from the Universidad Veracruzana, I'm doing my thesis about climate indices, and I've been using CDO for it, I have to say it is a great program, it is very useful. I'm a beginner so I'm not that familiarized with the program and I'm still learning.
The thing here is that I need to combine multiple NETCDFS in one file to calculate the CDD index but when I use cdo cat *.nc tpERA5reanalysis1980-2010.nc I get an error, wich is:

*cdo cat *.nc tpERA5reanalysis1980-2010.nc
cdo cat: 52%cdf_put_vara_double: name=tp type=NC_SHORT minval=-32766.000000 maxval=36820.000000

Error (cdf_put_vara_double): NetCDF: Numeric conversion not representable*

the variable is Total precipitation, I'm trying to concatenate 5 nc files in one. It is daily total precipitation data from 1980 to 2010. If there is any solution I could use, It would be very useful for me if someone could help me out. Thanks.
Cheers.
Gerardo