HAsmartirrigation: hourly sensor unavailable

v. 0.0.22 removed integration, removed component, restart, added component, restart, added integration -> hourly sensor unavailable:

log:

2020-05-30 13:10:17 ERROR (MainThread) [homeassistant.components.sensor] Error while setting up smart_irrigation platform for sensor
Traceback (most recent call last):
  File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 186, in _async_setup_platform
    await asyncio.gather(*pending)
  File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 295, in async_add_entities
    await asyncio.gather(*tasks)
  File "/usr/src/homeassistant/homeassistant/helpers/entity_platform.py", line 446, in _async_add_entity
    entity.async_write_ha_state()
  File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 297, in async_write_ha_state
    self._async_write_ha_state()  # type: ignore
  File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 320, in _async_write_ha_state
    state = self.state
  File "/config/custom_components/smart_irrigation/sensor.py", line 308, in state
    self._state = self.update_state()
  File "/config/custom_components/smart_irrigation/sensor.py", line 286, in update_state
    self.precipitation = self.get_precipitation(data)
  File "/config/custom_components/smart_irrigation/sensor.py", line 410, in get_precipitation
    retval = self.rain + self.snow
TypeError: unsupported operand type(s) for +: 'float' and 'str'