diff --git a/openevsehttp/__init__.py b/openevsehttp/__init__.py
index 0e94674..1af82d4 100644
--- a/openevsehttp/__init__.py
+++ b/openevsehttp/__init__.py
@@ -16,6 +16,7 @@
     AlreadyListening,
     AuthenticationError,
     MissingMethod,
+    MissingSerial,
     ParseJSONError,
     UnknownError,
 )
@@ -287,6 +288,28 @@ async def update(self) -> None:
                 self.url, self._update_status, self._user, self._pwd
             )
 
+    async def test_and_get(self) -> dict:
+        """Test connection.
+
+        Return model serial number as dict
+        """
+        url = f"{self.url}config"
+        data = {}
+
+        response = await self.process_request(url, method="get")
+        if "wifi_serial" in response:
+            serial = response["wifi_serial"]
+        else:
+            _LOGGER.debug("Older firmware detected, missing serial.")
+            raise MissingSerial
+        if "buildenv" in response:
+            model = response["buildenv"]
+        else:
+            model = "unknown"
+
+        data = {"serial": serial, "model": model}
+        return data
+
     def ws_start(self):
         """Start the websocket listener."""
         if self._ws_listening:
diff --git a/openevsehttp/exceptions.py b/openevsehttp/exceptions.py
index c384f24..6cff328 100644
--- a/openevsehttp/exceptions.py
+++ b/openevsehttp/exceptions.py
@@ -19,3 +19,7 @@ class MissingMethod(Exception):
 
 class AlreadyListening(Exception):
     """Exception for already listening websocket."""
+
+
+class MissingSerial(Exception):
+    """Exception for missing serial number."""
diff --git a/tests/test_init.py b/tests/test_init.py
index bd745c6..8691772 100644
--- a/tests/test_init.py
+++ b/tests/test_init.py
@@ -9,6 +9,8 @@
 from aiohttp.client_exceptions import ContentTypeError, ServerTimeoutError
 
 import openevsehttp
+from tests.common import load_fixture
+from openevsehttp.exceptions import MissingSerial
 
 pytestmark = pytest.mark.asyncio
 
@@ -737,3 +739,20 @@ async def test_set_divertmode(test_charger_v2, mock_aioclient, caplog):
         await test_charger_v2.divert_mode("normal")
     assert "Setting charge mode to normal" in caplog.text
     assert "Non JSON response: Divert Mode changed" in caplog.text
+
+
+async def test_test_and_get(test_charger, test_charger_v2, mock_aioclient, caplog):
+    """Test v4 Status reply"""
+    data = await test_charger.test_and_get()
+    mock_aioclient.get(
+        TEST_URL_CONFIG,
+        status=200,
+        body=load_fixture("v4_json/config.json"),
+    )
+    assert data["serial"] == "1234567890AB"
+    assert data["model"] == "unknown"
+
+    with pytest.raises(MissingSerial):
+        with caplog.at_level(logging.DEBUG):
+            data = await test_charger_v2.test_and_get()
+    assert "Older firmware detected, missing serial." in caplog.text
diff --git a/tox.ini b/tox.ini
index 3cee839..114271f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,9 +4,9 @@ skip_missing_interpreters = True
 
 [gh-actions]
 python =
-  3.8: py38, lint, mypy
+  3.8: py38
   3.9: py39
-  3.10: py310
+  3.10: py310, lint, mypy
 
 [testenv]
 commands =