@Dbagioni Maybe you did not map the device file (/dev/ttyUSB0) to the container, check this:
https://www.home-assistant.io/installation/raspberrypi#exposing-devices
During a multiple value assignment, the ValueError: not enough values to unpack occurs when either you have fewer objects to assign than variables, or you have more variables than objects. This error caused by the mismatch between the number of values returned and the number of variables in the assignment statement. This error happened mostly in the case of using python split function. Verify the assignment variables. If the number of assignment variables is greater than the total number of variables, delete the excess variable from the assignment operator. The number of objects returned, as well as the number of variables available are the same.
To see what line is causing the issue, you could add some debug statements like this:
if len(line.split()) != "xx":
print line
This will resolve the value error.
I'm afraid you're not going to get many answers to your question if you provide not more information...
type of heat pump, manufacturer
what are the current possibilities of controlling this heat pump
photo's
electric schema's
...
Try to give as much as possible (technical) information...