Hi, Are they connected with the trunk port that is carrying all of the VLANs? They should be able to communicate if they are. 
I have 2 powerconnect 2824. They have identical configurations. 1 switch will be upstairs and the other downstairs. There is cat5e between the rooms. Each switch has vlan 10,20,30 port 24 is trunk across all vlans. How do I join them?
How to connect 2 Dell powerconnect 2824