OrientDB, distributed load balancing

I am using OrientDB and faced a problem during working with replication. I have two servers with OrientDB and I can see that these OrientDB instances are communicating between each other. The problem is when I generate a batch of requests I can see that connections count increases only for one node (I can see this in OrientDB output). It seems that only one node services all requests. I read about load balancing in orientDB documentation and it suggests to set strategy like this

final ODatabaseDocumentTx db = new ODatabaseDocumentTx("remote:localhost/demo");
db.setProperty(OStorageRemote.PARAM_CONNECTION_STRATEGY, OStorageRemote.CONNECTION_STRATEGY.ROUND_ROBIN_CONNECT);
db.open(user, password);

But I can't use this way because I create ODatabaseDocumentTx object through OPartitionedDatabasePool.

Why are all requests serviced by one node? How can I configure load balancing?

Thanks