I am in the process of building a house. I have heard of the On Demand, instant hot water systems. Please let me know if any of you have used them, and if you consider them to be a worthwhile investment. It will be for two people and two small dogs, no kids or extended family. I am hoping it is not only cost effective but energy effective.I am also curious about radiant heating. I am located in North Carolina, so I don't have the extreme temperature changes of the north.

I stayed in singapore for a few years, where almost every household uses instant water heaters. In India, I tried looking around for such water heaters, either they are not to be found in the appliances stores or they have very few models. Why are tankless water heaters not as famous in India when compared to the storage water heaters?

We hooked it up but no hot water . The water pressure is good.

is Nat. Gas heaters for a 2 person familly effective enough for adequate hot water?

I only use my water heater for showers..is it more efficient to turn it on prior to use and then tur it off or does it use the same amount of gas if left on? Does it use alot of propane just ot have the pilot on?

Our ph is 7.8 -8.0 and a very high carbonate hardness. Have to replace heating elements often. Am unable to use a water softener to ease the situation. How does hard water affect the tankless heater?

We have a conventional electric hwh located in a large closet which we wish to convert into a 1/2 bath. To save space we thought of removing the old heater and installing an on-demand model.

My mother is concidering putting in the Hot water on Demand system. What would be the cost of this? Can someone give me some general information?

Additional Information
-There are just two of us home, my mother and I

We have an instant water heater, but it takes nearly 2 minutes for the water to even start getting warm. What is going on?