Default Timeout - Binding.ReceiveTimeout Property
The default is 10 minutes, so you always have to increase both of them to make a difference when using a reliable session.
stackoverflow - http://stackoverflow.com/questions/3037734/default-timeout-values-for-wcf-endpoints
microsoft url - https://msdn.microsoft.com/en-us/library/system.servicemodel.channels.binding.receivetimeout.aspx
Duplex Services
In WCF, there are some other techniques like Duplex Services to solve this.
https://msdn.microsoft.com/en-us/library/ms731064(v=vs.90).aspx
references :
http://stackoverflow.com/questions/19705804/implementing-a-web-service-callback
http://stackoverflow.com/questions/5739501/how-can-a-wcf-service-raise-events-to-its-clients