WCF: An error occurred while receiving the HTTP response to http:// - wcf

Question

We receive this error only on production server, but not always, sometimes it works.
It works always on development and test servers. On production server is a lot traffic and the returning data could be greater than on other services.
System.ServiceModel.CommunicationException: An error occurred while receiving the HTTP response to http://.../DefaultService.svc. This could be due to the service endpoint binding not using the HTTP protocol. This could also be due to an HTTP request context being aborted by the server (possibly due to the service shutting down). See server logs for more details. ---> System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a receive. ---> System.IO.IOException: Unable to read data from the transport connection: Eine vorhandene Verbindung wurde vom Remotehost geschlossen. ---> System.Net.Sockets.SocketException: Eine vorhandene Verbindung wurde vom Remotehost geschlossen
The relevant web.config part is:
<system.webServer>
<modules runAllManagedModulesForAllRequests="true" />
<security>
<requestFiltering>
<hiddenSegments>
<add segment="config" />
</hiddenSegments>
<requestLimits maxAllowedContentLength="104857600" />
</requestFiltering>
</security>
</system.webServer>
<system.serviceModel>
<serviceHostingEnvironment aspNetCompatibilityEnabled="true" />
<behaviors>
<serviceBehaviors>
<behavior>
<serviceThrottling maxConcurrentCalls="256" maxConcurrentSessions="256" maxConcurrentInstances="256" />
<!-- Set to "true" for WSDL access -->
<serviceMetadata httpGetEnabled="false" httpsGetEnabled="false" />
<serviceDebug includeExceptionDetailInFaults="true" />
</behavior>
</serviceBehaviors>
</behaviors>
<bindings>
<customBinding>
<!-- SOAP 1.2 (Http) -->
<binding name="CustomHttpBinding" receiveTimeout="00:15:00">
<binaryMessageEncoding>
<readerQuotas maxStringContentLength="2147483647" maxArrayLength="2147483647" maxNameTableCharCount="2147483647" />
</binaryMessageEncoding>
<httpTransport maxReceivedMessageSize="2147483647" maxBufferSize="2147483647" maxBufferPoolSize="2147483647" />
</binding>
</customBinding>
</bindings>
<services>
<service name="DefaultService">
<endpoint binding="customBinding" bindingConfiguration="CustomHttpBinding" contract="WebServiceInterfaces.IArgosDefaultWebService" />
</service>
</services>
</system.serviceModel>
In error message it says 'See server logs for more details'. In which server logs do we have to look for details?
And what could be the error?