The current water heater thread is very helpful and educational.
When we turn on the hot water in the kitchen, it takes a LONG time for the hot water to get to the faucet. The water
heater is on the other end of the house. I've often thought about putting a small water heater under the house
immediately beneath the kitchen sink. The idea of running two electric water heaters in a crawl space sounds expensive
from an operational perspective.
As an alternate, I thought about getting a small tankless water heater, but they're expensive. Plus, there seem to be an
increasing dissatisfaction with tankless units.
Another solution I considered was a recirculating pump that installs at the sink and, at the push of a button, pumps hot
water into the cold water line until the water in the hot water line gets hot. This unit was demonstrated on "This Old
House" a couple of years ago. There are differences in opinion as to whether that solution is a good one. A
recirculating pump that keeps the hot water line hot all the time does not seem like an efficient solution.
Since I haven't looked at this problem in a while, is there another reasonable solution that I have not considered? I've
come really close to biting the bullet and adding a second electric water heater in the crawl space. There is not enough
room in the kitchen to add one inside the house.
You can get a very small water heater that will fit under the sink. We
used them in restrooms at work, about 5 gallons or so. Put it in line
with the regular water heater so it has a larger demand capability.
I am in the same situation. What bothers me is most people here use
the "hot" water to do things like wash their hands even though the hot
water never arrives before they are done. In other words, they wash
their hands using the cold water coming from the hot water line. The
actual hot water now left in the line is then wasted. Oh well.
Maybe someone will have a better idea. (I agree constant
recirculation is a waste of energy). I've consider a small point of
use heater, but space is very tight. (The sink is in a kitchen island
with finished basement below). The recirculating pump with the button
would work, but people would still have to wait for hot water to
arrive. I bet they would press the button and then wash their hands
in cold water.
On Saturday, January 10, 2015 at 10:47:47 AM UTC-5, mcp6453 wrote:
I don't see why running a small, point-of-use water heater that only holds
a few gallons would be expensive. You'd have hot water right away. I guess
if you pull enough water, then the temp would drop a bit as the incoming
water mixes with whats there. But then when the hot water arrives from the
main heater, it would go back up. Probably an OK solution, would run off 120V,
maybe even off an existing circuit, etc.
They also have pump systems where they combine a timer with temp control. So
the pump circulates it only during the times you tell it to and when the temp
requires it, avoids having it run 24/7. Biggest problem with a pump is if it
uses the cold water line for a return. Then you have that tepid, crappy hot
water coming out in your drinking water. OK for a bathroom, but not what I'd
want for a kitchen.
No one in this thread has mentioned applying pipe insulation.....
Yea, it still takes some time for the hot water to arrive, but it helps.
The OP is not alone. We ALL have this problem. The further the pipes
run, the longer it takes to get the hot water to the sink. It's just
life. Sometimes things cant be changed.... (at least not affordably).
The water heater could be moved to a more central location, but that
costs money and requires a place to put it.
Our ancestors had to build a fire in a wood stove, then wait for a
kettle of water to get hot. I guess I can wait 40 seconds for the hot
water to arrive at the sink..... And since my bathroom sink is closer
to the heater, I wash my hands in there, not the kitchen sink....
As far as the OP, I would NOT suggest putting a secondary heater in a
crawlspace, unless it's a heated crawlspace (which I doubt). That will
just lead to other problems, like frozen pipes and/or having to run heat
tape and pay more on the electric bill.
You can get faucets with a built in heater, no tank. Here are some
On Sunday, January 11, 2015 at 6:48:57 AM UTC-5, dadiOH wrote:
All those are 3KW and I don't see any tables of flow rates vs temp rise.
At some very low flow rate, the single faucet ones might do something,
but I wonder if it's even enough to be able to wash your hands. The other
ones that come up in that search that are separate from the faucet are
snake oil. 3KW and it says "ONE HEATER MULTIPLE POINTS ENTIRE HOUSE"
Even a real tankless for a couple of sinks uses 4X that power, ie you
can't get a decent temp rise and flow rate from 3KW.
Those on that link are very interesting. Sounds like a great solution
if they work as claimed and don't send the electric bill through the
roof. Anyone here ever used one like these?
Stay away from these Old House gadgets. Adding a recirc pump will add
much cost, plus you'll have to do regular maintenance, watch out for
leaks, etc. Stick with an instant heater or install a parallel pipe to
get you more flow.
You could have a problem like mine...
I also have weak hot water flow everywhere. Pressure at the water
heater outlet is normal. My bad -- I installed a new water heater in
the garage at the far end of the house, and just plumbed into the
existing piping. This means hot water goes first to the bahtrooms
quickly, then to where the old water heater was, then to the kitchen.
Lots of elbows and smaller pipe which reduces the pressure & flow.
Will need to crawl under there next summer and install a straight shot
On Sunday, January 11, 2015 at 12:45:12 PM UTC-5, Snuffy Hub Cap McKinney wrote:
All of them are 3KW. If all you need is very slow flow at one faucet,
it could work, especially for cases like the OP, where you could
put up with low flow for the first minute, until hot water from the
water heater gets there. But for sure the ones in that link that aren't part
of a faucet, that claim to be able to do tankless for a whole house, etc are BS.
I don't believe the pumps require any maintenance. If the
pump can leak, so can the faucet heater gizmo. And I'd bet those things
on the link are all crap. They are no-name stuff from China, selling on
Ebay. If such a product exists from a real company, I'd bet it costs
as much or more than the pump solution. The only beef I have with the
pumps is if you use the cold water pipe as a return, you put tepid, crappy
water from the WH into the cold water line. From there, depending on
the line, it can go to the next glass of drinking water, ice cubes, etc.
I have not but a friend had one, used it mostly to make a quick cup of
I never paid much attention to it but IIRC the flow rate was not very
high; still, it was high enough to get almost instant hot water.
On Monday, January 12, 2015 at 6:05:20 AM UTC-5, dadiOH wrote:
Those units are 3KW.
With 3KW you can get an 80F temp rise with a flow rate of a quart a minute.
So if the water in the pipes is at 50F, you can get 130F, ie typical hot
tap water temp at a quart a min. Of course the other problem is that 3KW
requires 25A at 120, or alternatively 240V, which means you likely have to run
a new circuit, just for the heating faucet. Once you have to do that,
it would seem to me there are better solutions, eg a typical small tankless
that can provide much higher flow rate.
Same issue at my house. A cheap and simple remedy for me was simply
covering the pipes with that tubular foam insulation. No, it won't
keep the water hot for long - but it will keep it warm to coolish in
between uses, meaning three quarters of the time, the water
temperature is comfortable enough for hand washing. There's still the
lag when the faucet hasn't been run for a long time, but for most of
the daily routine it's much better than it was prior to wrapping the
hot water pipes.
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