Ok - I worked my way through some really crude python and I have it displaying some information regarding the water, and printing to the REPL. Now that I can actually read it for what data it is supposed to be showing, It appears that I may have some differences from what @suva shows.
As it relates to index 18 & 19 (flow) on the water side. It seems that my water flow is actually index 18, as index 19 never changes for me. Index 19 is always zero. I confirmed that the front panel shows the value I am calculating on index 18 in the code, back to GPM.
Also, index 13 - that value seems strange to be inlet temperature. Guess I will have to keep watching and comparing that value to the front panel of the unit and see what it says.