Herbert Graf wrote:
> On Fri, 2011-05-06 at 10:48 -0400, Olin Lathrop wrote:
> > William Couture wrote:
> > > My wife has decided that we should get a tankless hot water heater to
> > > save energy.
> >=20
> > I'm not sure they save energy. I can see some reasons they might take
> > more, but other reasons they might take less. The main selling point as=
 I
> > understand it is that hot water is always available. You never run out.
>=20
> The main theory on "save energy" is that fact that you don't have a tank
> of hot water that has to be kept hot all the time.

Even a "tankless" heater keeps some part of itself hot all the time. The
theory is that that part is much smaller than a water tank and therefore
has less surface area through which to lose heat, and it also can be better
insulated.

The fundamental limit on a hot water tank is how much hot water you're like=
ly
to need at once. The fundamental limit on a tankless system is the total ra=
te
(GPM vs. temperature) at which you need hot water.

-- Dave Tweed
--=20
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.