diff --git a/homeassistant/components/flexit/climate.py b/homeassistant/components/flexit/climate.py
index 838d2c934f9..dbe1e060a12 100644
--- a/homeassistant/components/flexit/climate.py
+++ b/homeassistant/components/flexit/climate.py
@@ -177,9 +177,7 @@ class Flexit(ClimateEntity):
         self, register_type: str, register: int
     ) -> int:
         """Read register using the Modbus hub slave."""
-        result = await self._hub.async_pymodbus_call(
-            self._slave, register, 1, register_type
-        )
+        result = await self._hub.async_pb_call(self._slave, register, 1, register_type)
         if result is None:
             _LOGGER.error("Error reading value from Flexit modbus adapter")
             return -1
@@ -197,7 +195,7 @@ class Flexit(ClimateEntity):
         return result / 10.0
 
     async def _async_write_int16_to_register(self, register: int, value: int) -> bool:
-        result = await self._hub.async_pymodbus_call(
+        result = await self._hub.async_pb_call(
             self._slave, register, value, CALL_TYPE_WRITE_REGISTER
         )
         if not result: