Why can't I access a webserver through a load balancer on my local network?

When I try to use curl (or wget, lynx, etc) to connect from a server on our local network to our website, which is on a local server behind a CoyotePoint load balancer, curl fails. Ping does not have this problem.

When I curl directly to any of the servers behind that load balancer (from and to the same local network), I also have no problem. It doesn't matter whether the local server I'm curling from is behind the load balancer or not.

Does anyone have any idea why I can't access my webserver through the load balancer on my local network?

Edit: additional information:

The error message from curl:

*   Trying [ip address]... connected
* Connected to [web address] ([ip address]) port 80 (#0)
> GET / HTTP/1.1

> User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.12.6.2 zlib/1.2.3 libidn/1.9 libssh2/1.2.4
> Host: [web address]
> Accept: */*
> 
* Closing connection #0
* Failure when receiving data from the peer
curl: (56) Failure when receiving data from the peer

The IP address is the correct external address, not the internal network IP.

I am attempting to curl using the web address, not an IP address. That web address resolves to the correct IP address to connect to the site (externally) through our load balancer.

As I understand our networking (I'm obviously no expert at this) all of our servers and our load balancer are all on the same network.