See "Timeouts in WCF and their default values" http://blogs.msdn.com/b/hongmeig/archive/2010/03/06/timeouts-in-wcf-and-their-default-values.aspx
Timeouts on binding-SendTimeout, ReceiveTimeout,
OpenTimeout and CloseTimeout. They can be set easily either through
config or code on the Binding. The default value for those are 1
minute.
ServiceHost has OpenTimeout and CloseTimeout. Default for OpenTimeout
is 1 minute, and default for CloseTimeout is 10 seconds.
Timeouts on client side channel. There is an OperationTimeout, which
you can set it by casting the channel to IContextChannel. The default
for this is also 1 minute. Ttimeout on tcp transport, called
ChannelInitializationTimeout, and its default value is 5 seconds.
ASPNET. There are shutdown timeout, just like the service host close
timeout, default is 90 seconds. ExecutionTimeout, just like our
operation timeout, default is 110 seconds.