I have a new in the box TK1. I know this model has not been manufactured in a number of years. Were there any issues that one would want to know about with this model? It has never been out of the box.
Thanks!
Only real difference is that you are not going to have the new and improved heat exchanger. Other than that I couldn't find any real differences.
Now a word of advice if you decide to install this I recommend calling a certified Takagi installer. They will make sure your unit is LP or NG, and install the unit properly for you. Also here is the flow rates of the unit for you to ensure it will do the job for your home.
Incoming water Temp_______ΔT rise to reach 120º ________Flow Rate
40º ------------------------------------------- 80º ----------------------- 3.4 GPM
70º ------------------------------------------- 50º ----------------------- 5.4 GPM