You don't mention what load balancing technology you are using, so I am going to assume Windows Network Load Balancing (NLB). There are a collection of cmdlets that can help you control the load balancing state of your server.
The cmdlets are described here: Network Load Balancing cmdlets in Windows PowerShell
To use the commandlets you'll need to first import the module.
Import-Module NetworkLoadBalancingClusters
Then you can see all the commands available to you:
Get-Command –module NetworkLoadBalancingClusters