"Clark W. Griswold, Jr." 73115 dot 1041 at compuserve dot com wrote in
message ...
Ron Hammon wrote:

The big, ol' tank is not the primary source of heat loss. It is the
piping running for many yards in an unheated crawlspace, for example.
When you open a hot water fauct and wait on the flow "get hot", this
demonstrates the lost heat. Since heat loss is reduced as the pipes
cool down, I expect that things would actually IMPROVE with less hot
water use, not get worse. (Of course, eventually, it would still cost
to maintain tank temperature with NO hot water use. So, the "sweet
spot" is in the middle somewhere.)

All true. But here's the deal: Most people who discover tankless heaters
for the
first time think they have discovered an amazing secret that is going to
save
them hundreds, if not thousands in energy costs.

What they are thinking is that they will replce their storage tank heater
with a
demand (tankless) heater. In that situation, you can exclude pipe loss as
it is
the same for both types of heaters.

I would think that a big reason for putting in a tankless heater is that it
is smaller and therefore capable of
bieng installed closer to the long run sink and thus giving less warmup
time/loss.
and thus is a convenience even more than an energy saving.