wrote in message
: > years ago i thought Bullshit but i had a friend that had a
camp on the
: > lake where i have one and he only run his hot water tank
while he was
: > gone. if he never went to the camp it cost him $10.50 to run
: > water tank on very low while gone. He and I went up there and
: > blanket on his electric hot water tank and then the next bill
: > with no body using it. That is a 28% cut in useage of the
: > at stand still job with no useage !
: Years ago the tanks were not insulated as well as they are
: Another factor is the temperature of the building while not
occupied. If it
: was kept very low, there would be more heat transfer at 50
degrees than at
: 70 degrees.
: Still another factor for part of the year is total heating
cost. If the
: water heater gives up some heat to the room, the central
heating system will
: have to put out that much less.
: While some added insulation may help, I doubt anyone will
: near the 28% the fellow in your example was able to get.
Easy enough to empiracally figure out how good the insulation is;
put a partial wrap around the heater, give it a day or so, then
slip your hand in under the insulation: you might be pretty
surprised at how hot it is in there.
Both heater and pipes should be wrapped; one without the other
is much less efficient.
Water heater insulations just are NOT very good in my experience;
new or not, there isn't much difference. And there's a lot of
loss in the first few feet of pipe on the output side too, less
on the input side, much less if plastic pipe.