Due to the rapid growth of Call Center Companies, alternatives for balancing calls between multiple servers where the agents are connected (ACD <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> servers), and that allow the increase of the operation capacity without compromising the performance and quality of service are needed. Currently, load balancing algorithms usually address the problem for a set of geographically separated Call Centers (VCC: Virtual Call Centers), which are connected through data links and whose metric is the bandwidth. There are also load balancers for SIP <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> servers that implement algorithms focused on this protocol. In this paper, a load balancer is modeled for Call Center systems which enables the distribution of calls between multiple ACD servers that are interconnected in a Local Area Network (LAN). This work was done by implementing Generalized Round Robin (GRR) algorithm and Minimum Expected Delay (MED) algorithm under two scenarios: homogeneous, i.e., same number of agents connected to multiple ACD servers; and heterogeneous i.e., different number of agents connected to multiple ACD servers. Finally we present a hybrid algorithm called Minimum Expected Delay Modified (MED) that improves agent utilization in each of ACD servers.