Okay, so I'm at the jobsite and hooked up the laptop to the Jandy serial adaptor and started using hyperterminal. I am able to control the state of various pool functions without issue using hyperterminal.

As an example they have a waterfall that is attached to Aux. 4. I send #AUX4=0 and it turns it on and #AUX4=1 turns it off. I then load the exact same string into ID and nothing. I have confirmed that the wiring on the cat5 leading to the Jandy device is correct. I know that the Jandy device is straight through and doesn't require a null modem adaptor. Just for grins I did temporarly install a null modem adaptor to to be sure. I am now at a complete loss! Any ideas guys???