diff --git a/S7.Net/PLC.cs b/S7.Net/PLC.cs
index 3a73b4c..b7ede94 100644
--- a/S7.Net/PLC.cs
+++ b/S7.Net/PLC.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.IO;
 using System.Linq;
 using System.Net.Sockets;
 using S7.Net.Protocol;
@@ -242,6 +243,16 @@ namespace S7.Net
             }
         }
 
+        private Stream GetStreamIfAvailable()
+        {
+            if (_stream == null)
+            {
+                throw new PlcException(ErrorCode.ConnectionError, "Plc is not connected");
+            }
+
+            return _stream;
+        }
+
         #region IDisposable Support
         private bool disposedValue = false; // To detect redundant calls
 
diff --git a/S7.Net/PlcAsynchronous.cs b/S7.Net/PlcAsynchronous.cs
index 7730b3a..3e523d8 100644
--- a/S7.Net/PlcAsynchronous.cs
+++ b/S7.Net/PlcAsynchronous.cs
@@ -5,7 +5,6 @@ using System.Linq;
 using System.Net.Sockets;
 using System.Threading.Tasks;
 using S7.Net.Protocol;
-using System.IO;
 using System.Threading;
 using S7.Net.Protocol.S7;
 
@@ -502,15 +501,6 @@ namespace S7.Net
             }
         }
 
-        private Stream GetStreamIfAvailable()
-        {
-            if (_stream == null)
-            {
-                throw new PlcException(ErrorCode.ConnectionError, "Plc is not connected");
-            }
-            return _stream;
-        }
-
         private async Task<COTP.TPDU> RequestTpduAsync(byte[] requestData, CancellationToken cancellationToken = default)
         {
             var stream = GetStreamIfAvailable();