Under cabinet compact water heater
- Thread starter SamSpade
- Start date
PeoplesElbow
Well-Known Member
The hardest part is running electricity or gas to it.
Clem72
Well-Known Member
Easy to install, especially if you already have a circuit nearby (maybe for garbage disposal). But most of these systems keep the water at or near the desired temp so you can expect to see a measurable impact on your electric bill. So if you get one, may as well use it as much as possible.
No they don't.
itsbob
I bowl overhand
I've seen two different kinds.. small tankless heaters and small tank type heaters..
The small tank type you leave off, then (for example) you sit down to eat dinner you turn on the water heater and when you're done eating your water is heated and ready to use..
The other, it's instant on, and bottomless..
There are also "recycler" systems where you consistently cycle water back to the heater, and hot water is always in the water lines leading to your faucet (Can't imagine that's very efficient unless you do like above.. turn it on 5 - 10 minutes prior to needing it).
Gas would be an issue for a tankless.. not sure, but I would THINK a small tankless heater could run off 110, and most sinks have an outlet you can tap off of either close by or even under the cabinet.
itsbob
I bowl overhand
Wow, Amazon has under cabinet Tankless for $100 or less...
New build these would be so worthwhile.. considering you'd only have to run cold water lines throughout the house.. 1/2 the plumbing, 1/2 the cost.
You're going to run electric to all the rooms anyways, so running a 240v vice 120v to each room can't be too much more (gas would be more costly of course, but new construction how much more??)..
and the money you'll save over the years with tankless water heaters under every sink??
New build these would be so worthwhile.. considering you'd only have to run cold water lines throughout the house.. 1/2 the plumbing, 1/2 the cost.
You're going to run electric to all the rooms anyways, so running a 240v vice 120v to each room can't be too much more (gas would be more costly of course, but new construction how much more??)..
and the money you'll save over the years with tankless water heaters under every sink??
GWguy
*
That is an outstanding thought. If I were ever to build or retrofit, I'd consider that.
black dog
Free America
You better look at the specs for those heaters, 0.5 gallons per minute, and what temperature you get out of it will depend on what temperature you well or city water is when it enters the heater. And it's tough to take a shower with 0.5 gallons per minute of maybe hot water.
Look at the specs of these electric tankless heaters, in most cases you need alot more electric than you think. Check water temp in and water temp out along with how many amps of 120 or 240 you need to run it.
Clem72
Well-Known Member
Yes they do, if you are talking about the separate tap instant 200+ degree dispensers, as I believe was the point (you don't make coffee or tea with 120 degree water).
https://www.amazon.com/InSinkErator...keywords=kitchen+sink+instant+hot+water&psc=1
Not the small regular instant water heaters like you were pointing out.
itsbob
I bowl overhand
That was an example if you only wanted 120v .. cheaper install.
There were many more that were 240V for 4 - 6 GPM.. much more than a sink faucet will use.
PeoplesElbow
Well-Known Member
One that that will help and is almost free is insulating the pipes too the sink.
It doesn't help first thing in the morning after the water has been off for a while but if the hot water was used 10 mins ago it sure does. I insulated all of my pipes in my crawl space and behind the walls when I remodeled the bathroom and it has made a significant difference in time to get hot water at various points throughout the day.
It doesn't help first thing in the morning after the water has been off for a while but if the hot water was used 10 mins ago it sure does. I insulated all of my pipes in my crawl space and behind the walls when I remodeled the bathroom and it has made a significant difference in time to get hot water at various points throughout the day.
black dog
Free America
And i will say this again Bob, look at the specs for what is needed for installation, to run a tankless electric heater at 3 to 6 GPM you will need 60 to 150 + amps of electrical service for each heater. And the true temperature output will be determined by inlet water temperature along with the amperage of the heater.
When inlet temperature drops so does outlet temperature.
If electric tankless are the Shizzle, how come everyone doesn't install a large one when they replace the tank heater.
( Pessssttttttt.. because they would have to heavy up with another 200 amp service just to run the electric tankless whole house heater.
That's why almost all tankless heaters are NG, propane or fuel oil.
black dog
Free America
I have a insta-hot, it keeps about a quart of water hot at my kitchen sink. It keeps water at 200°. What we are talking about is tankless electric heaters at point of use.
itsbob
I bowl overhand
You're right, but it's much easier and cheaper to run an additional electric line instead of gas line for an under the sink installation.. NOTHING saying they can't also do a gas under the sink tank less, or even a recycling system with a whole house gas tank less..
Had a furnace in a townhouse that used a similar set up (recycling system) to supplement the heat pump with hot water in the heat exchanger using a tank less hot water heater. Ensured you weren't running cold water through your furnace for the first 5 minutes the fan was on.
But again, the installation cost of all the additional plumbing, the water heater installation and the water heater itself would get expensive.
Clem72
Well-Known Member
That's what you and bob are talking about. I didn't see sam clarify if that is what he was talking about.
Chris0nllyn
Well-Known Member
They're horrible.
You need at least 240V, or a high-amperage 120V circuit (unlike a garbage disposal) to get it to consistently give you hot water.
We have one in our construction trailer and hot water lasts long enough to wash dishes from lunch, and that's it.
You may be better off getting a recirculation pump and use the water heater you have.
You need at least 240V, or a high-amperage 120V circuit (unlike a garbage disposal) to get it to consistently give you hot water.
We have one in our construction trailer and hot water lasts long enough to wash dishes from lunch, and that's it.
You may be better off getting a recirculation pump and use the water heater you have.
black dog
Free America
Some here just don't believe that a simple 120v plug in tankless will give you vast amounts of steamy hot water.
It just takes too much amperage to get 120° water from a electric tankless other than maybe to wash your hands. And even when the large units are installed in a home when the water load picks up they are incapable of delivering the needed hot water. Junk..
They tried large electric tankless heaters in two cottages at Solomans Navy Rec a few years back, they pulled them out within a few weeks and installed Propane Rinnai tankless units.
In alot of homes a return ( loop ) can be installed to the hot water heater and radiant will circulate the water. Most folks will close the valve after a few months of elevated cost of running the water heater.
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