Informed opinions on inline water heaters requested.

[Gawdzilla Sama]

I haven't heard about them in quite a few years, suggesting that they had serious issues. Are they still a thing, do they show an advantage over running the tap for a few minutes? Are there alternatives available now?

Thanks in advance for any help.

 

[Write4U]

I haven't heard about them in quite a few years, suggesting that they had serious issues. Are they still a thing, do they show an advantage over running the tap for a few minutes? Are there alternatives available now?

Thanks in advance for any help.

For one I believe they are used in big self-contained travel trailers. Usually propane heated.
It certainly reduces precious water use. I think residential applications use electricity or gas heated "geysers".

I know they are/were popular in Europe. It can be a very efficient low cost hot water system.

 

[Gawdzilla Sama]

My bathrooms are right over the cold water heater, so the "lag" is minimal. But the kitchen is thirty+ feet from the heater and the lag is annoying. I'm pumping the cold water out of the pipes (and down the drain) and then heating the pipes with the hot water I want for the kettle. So, I'm looking to put in a smallish unit, dishwasher demand being highest, an undersink model. There's a large empty space suitable for a small unit under the counter beside the sink.

 

[billvon]

My bathrooms are right over the cold water heater, so the "lag" is minimal. But the kitchen is thirty+ feet from the heater and the lag is annoying. I'm pumping the cold water out of the pipes (and down the drain) and then heating the pipes with the hot water I want for the kettle. So, I'm looking to put in a smallish unit, dishwasher demand being highest, an undersink model. There's a large empty space suitable for a small unit under the counter beside the sink.

If you are doing that - get a recirc pump instead. That way you don't need a heater, with all the hassle that involves (like a propane line or a 40A circuit.)

 

[Jeeves]

We've had a propane one in the house for 19 years; it's needed cleaning once and relighting a couple of times. It has never stopped working and we've never had a problem... except for a little water drip that's developed recently: its little catch-basin needs emptying every day now. We'll probably have to call out a gas service person pretty soon, and they're expensive. It takes up very little wall-space above the freezer, which we couldn't have put in the utility room if we had a water-tank.
It does need gas line and chimney.

 

[RainbowSingularity]

It can be a very efficient low cost hot water system.

that there is the problem, all the power companys hate them.

 

[Write4U]

https://www.homedepot.com/p/Bosch-7-Gal-Electric-Point-of-Use-Water-Heater-ES-8/206428468?cm_mmc

 

[Gawdzilla Sama]

If you are doing that - get a recirc pump instead. That way you don't need a heater, with all the hassle that involves (like a propane line or a 40A circuit.)

Help me here, does that continuously cycle water through the pipes so it's always hot? If so, wouldn't that be heating the pipes all the time? I ask because I don't know.

 

[Gawdzilla Sama]

https://www.homedepot.com/p/Bosch-7-Gal-Electric-Point-of-Use-Water-Heater-ES-8/206428468?cm_mmc

I don't need that much hot water at one time typically, so the capacity is reasonable for my needs. I'll check it out. I also would need to confirm how much water the dishwasher uses. Thanx.

 

[RainbowSingularity]

Help me here, does that continuously cycle water through the pipes so it's always hot? If so, wouldn't that be heating the pipes all the time? I ask because I don't know.

no
it runs on pipe presure and/or pumping.
it heats the water as it flows as you turn on the tap.
i beleive there are systems that can actually pump the water also. they are quite expensive and more complex.

it heats the water in a pipe that sits in your wall and the pipe runs directly to what ever you want, a splitter or such like.

immediate heated water with only a meter or soo to travel at a much lower cost.
same as always, insulating your pipes is considered a basic manditory idea unles ur only piping to a single outlet tap and fairly close.

see the blue & red pipes.
mains inlet to blue
outlet to hot tap red.
turn on the water tap and the presure triggers the hearter to kick in.

if the heater gets turned on and the water is not flowing, it has the potential to explode and or cause a fire.
but thats quite unlikely. there are saftey type switches and such like.

 

[Gawdzilla Sama]

Thanks, do you have a link handy? If not I'll Google for it.

 

[billvon]

Help me here, does that continuously cycle water through the pipes so it's always hot? If so, wouldn't that be heating the pipes all the time? I ask because I don't know.

You can set it up that way, but that would waste a lot of energy.

There are different kinds of pumps out there. Some pumps run on a timer and only cycle the water during certain times of the day (right before you do dishes for example.) Some use a pressure switch to turn on when you turn on a faucet, but of course there is lag with those systems. Our system has a remote control button you push, and the pump runs until the water's hot and then shuts off.

 

[Gawdzilla Sama]

Ah, okay. We need hot water in the kitchen at most eight to ten hours a day. Anything after that we'd fall back to "run until hot" mode.