Point Of Use Water Heaters

[Chesterton]

I just recently learned of these things. Anybody here use one? It's claimed they deliver hot water "instantly". Is it really instant? In the kitchen and shower, the water heats up reasonably quick, but at the sink where I shave it can take over 3 minutes for the water to heat on cold winter days.

Also, while browsing these online, I've noticed they're sometimes referred to as "hot water heaters", lol. That's not what I need. I need a cold water heater.

 

[sandman]

I just recently learned of these things. Anybody here use one? It's claimed they deliver hot water "instantly". Is it really instant? In the kitchen and shower, the water heats up reasonably quick, but at the sink where I shave it can take over 3 minutes for the water to heat on cold winter days.

Also, while browsing these online, I've noticed they're sometimes referred to as "hot water heaters", lol. That's not what I need. I need a cold water heater.

POU and tankless are the same, but different.

POU would refer to a tankless just below the sink.

A tankless water heater is generally centrally located and supplies heated water to various locations. The time involved depends on the length of run from the unit.

If you have a POU at your bathroom sink and it’s taking 3 minutes there could be a problem with it. If it is a retrofit it probably run on 120 but it still should be quicker that.

 

[Tuur]

A brother-in-law is having them installed in a house that's undergoing major rebuilding. That's good, because POU water heaters draw a lot of amps, and the wiring and breakers need to be able to handle it.

Other than that, I have more questions than answers. Specifically the problem of hard water. Hard water will precipitate out onto heating elements, resulting in a coating on the elements and a pile of sediment in a water heater tank. There's supposedly a way to prevent that, but uncertain how well that works. In a POU water heater, it's going to have to bring water to temperature practically instantaneously, which has me wondering if hard water presents a significant problem.

 

[JosephZ]

I just recently learned of these things. Anybody here use one? It's claimed they deliver hot water "instantly". Is it really instant?

POU water heaters are commonly found in hotels and Condos in the Philippines. I've stayed in many over the years when traveling and they always provided hot water on demand and were sufficient for showering or whatever. Most of the ones I have used have a dial for setting the water temperature to the desired level.

 

[Chesterton]

A brother-in-law is having them installed in a house that's undergoing major rebuilding. That's good, because POU water heaters draw a lot of amps, and the wiring and breakers need to be able to handle it.

Other than that, I have more questions than answers. Specifically the problem of hard water. Hard water will precipitate out onto heating elements, resulting in a coating on the elements and a pile of sediment in a water heater tank. There's supposedly a way to prevent that, but uncertain how well that works. In a POU water heater, it's going to have to bring water to temperature practically instantaneously, which has me wondering if hard water presents a significant problem.

I hadn't thought of that. We have very hard water here, which I've heard is good for drinking, but bad for appliances and plumbing.

POU water heaters are commonly found in hotels and Condos in the Philippines. I've stayed in many over the years when traveling and they always provided hot water on demand and were sufficient for showering or whatever. Most of the ones I have used have a dial for setting the water temperature to the desired level.

So you use turn a dial on the heater rather than the faucet knob?