On (16 Jun 96) Jim Dunmyer wrote to Ian Woofenden...
 JD> You're not "using energy around the clock", just kicking on
 JD> the burner/element for a short time every now and again.
Right. But it is having to keep it hot all the time. It's more like
a fridge than a water pump  , as loads go.
 JD> The actual wastage is dependant on several factors: how much
 JD> and how often you use hot water, and how well-insulated the
 JD> tank is, along with the length of the pipes between the heater
 JD> and the point of use. If your heater is fairly close to the
 JD> point of use, and you use water several times during the day,
 JD> you'll save pretty much nothing by going to a demand-type
 JD> unit. OTOH:, if you often go 24 hours without using any hot
 JD> water and the tank would be 30+ feet from the point of use, a
 JD> demand heater would save "some" money.
 JD> When you consider the other costs and increased complexity of
 JD> the demand heater, you'll find that it's not the
 JD> be-all/end-all that many folks think.
I tend to agree with you that demand heaters are perhaps overrated
by the RE industry. But OTOH, I think if more were bought and used
the designs would improve. And I expect in most cases they do save
energy over a tank heater. I would like to see hard figures though.
Tank heaters seem to be "the way we've always done it", which often
isn't the best way. I still stand by the theory that it makes more
sense to heat water only when you need it instead of always heating
20-60 gallons just in case...
Take care,
Ian
                        Ian
... You can lead a guitar to water but you can't tuna fish.                   
 
... "Even if you're on the right track, you'll get run over if you just sit
there."  - Will Rogers
--- PPoint 1.96
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