How hot will the water get?

The HOTTAP has a max temperature output of 50 degrees Celsius (122F). The temperature rise is dependent on the settings you have the HOTTAP on.

Low water & high gas = 35C increase (95F)
High water & high gas = 20C increase (68F)

For example, if you had the HOTTAP set at Low water and high gas and you were drawing water from a lake that was 10C (50F), the output would be 45C (113F).