Try this on your context:
public class MyDatabase : DbContext
{
public MyDatabase ()
: base(ContextHelper.CreateConnection("Connection string"), true)
{
((IObjectContextAdapter)this).ObjectContext.CommandTimeout = 180; // seconds
}
}
If you want to define the timeout in the connection string, use the Connection Timeout
parameter like in the following connection string:
<connectionStrings>
<add name="AdventureWorksEntities"
connectionString="metadata=.\AdventureWorks.csdl|.\AdventureWorks.ssdl|.\AdventureWorks.msl;
provider=System.Data.SqlClient;provider connection string='Data Source=localhost;
Initial Catalog=AdventureWorks;Integrated Security=True;Connection Timeout=60;
multipleactiveresultsets=true'" providerName="System.Data.EntityClient" />
</connectionStrings>
Source: How to: Define the Connection String