diff --git a/homeassistant/components/rflink/__init__.py b/homeassistant/components/rflink/__init__.py
index 3cff3beed3c..68783c3426a 100644
--- a/homeassistant/components/rflink/__init__.py
+++ b/homeassistant/components/rflink/__init__.py
@@ -203,25 +203,28 @@ async def async_setup(hass, config):
     # TCP port when host configured, otherwise serial port
     port = config[DOMAIN][CONF_PORT]
 
-    # TCP KEEPALIVE will be enabled if value > 0
-    keepalive_idle_timer = config[DOMAIN][CONF_KEEPALIVE_IDLE]
-    if keepalive_idle_timer < 0:
-        _LOGGER.error(
-            "A bogus TCP Keepalive IDLE timer was provided (%d secs), "
-            "default value will be used. "
-            "Recommended values: 60-3600 (seconds)",
-            keepalive_idle_timer,
-        )
-        keepalive_idle_timer = DEFAULT_TCP_KEEPALIVE_IDLE_TIMER
-    elif keepalive_idle_timer == 0:
-        keepalive_idle_timer = None
-    elif keepalive_idle_timer <= 30:
-        _LOGGER.warning(
-            "A very short TCP Keepalive IDLE timer was provided (%d secs), "
-            "and may produce unexpected disconnections from RFlink device."
-            " Recommended values: 60-3600 (seconds)",
-            keepalive_idle_timer,
-        )
+    keepalive_idle_timer = None
+    # TCP KeepAlive only if this is TCP based connection (not serial)
+    if host is not None:
+        # TCP KEEPALIVE will be enabled if value > 0
+        keepalive_idle_timer = config[DOMAIN][CONF_KEEPALIVE_IDLE]
+        if keepalive_idle_timer < 0:
+            _LOGGER.error(
+                "A bogus TCP Keepalive IDLE timer was provided (%d secs), "
+                "it will be disabled. "
+                "Recommended values: 60-3600 (seconds)",
+                keepalive_idle_timer,
+            )
+            keepalive_idle_timer = None
+        elif keepalive_idle_timer == 0:
+            keepalive_idle_timer = None
+        elif keepalive_idle_timer <= 30:
+            _LOGGER.warning(
+                "A very short TCP Keepalive IDLE timer was provided (%d secs) "
+                "and may produce unexpected disconnections from RFlink device."
+                " Recommended values: 60-3600 (seconds)",
+                keepalive_idle_timer,
+            )
 
     @callback
     def reconnect(exc=None):