We are in Indiana and on city water.

I am looking for recommendations as to brand / model.

My other question is do all of these work by adding x degrees to the incoming water, or are there brands which vary the heat applied to hit a target temperature? The temperature of the incoming water varies quite a bit form winter to summer.

Good to talk to another Hoosier - Go Colts!

All tankless heaters vary the amount of heat up to a point. The point that they stop is the maximum capacity of the heater. You design for that worst case.

So, for example, if you have a faucet that is 2gpm and you are in central Indiana where the water temp can be 35 degrees F in the winter, you will need a heater that's capable of heating 2gpm 70 degrees (to 105). If it will do that, it will be fine the rest of the year.

For Point of use, I would expect that you are thinking electric. I would still plumb that in series with the hot water - rather than from the cold water line.

All electric heaters are 100% efficient (close enough) - one brand isn't going to get more heat out of the same amount of electricity than another brand. You will need to size it according to the above example, though.

Just an interesting FYI: I know that many gas tankless units will not only vary the amount of heat, but they will throttle the water flow also in order to maintain the proper temperature.

Thank you for the reply. You are right that I am looking at electirc. I am guessing it will be 240w.

You have helped to confirm what I qas thinking - 2gpm with a max rise of 70 degrees. I need to search more. The Point of Use tankless electric heaters I have researched so far do not appear to have that range.

My husband originally thought we should plumb it with the hot water line- but the first couple we looked at were marked as requiring plumbed to cold only.

I can't wait for Sunday. I have declared we will stop the renovtion work long enough to watch the game. (Here's to a healthy Freeney.)