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re: water heater blankets
9 dec 2005
edwin pawlowski wrote:
>> wrote:
>>>others tell me that water heaters manufactured in the last
>>>five years are so well insulated to begin with that if they are
>>>installed in heated space, a blanket is a waste of time and money and
>>>will produce negligible energy savings.
>>>
>>>what do you think?
>
>i think they are correct.
wrong!!! if grainger's $204 1pz75 50 gallon 19" diam. x 56.5" tall electric
heater with 27.4 ft^2 of r11.5 surface loses 8765h(120-65)27.4/11.5 = 1.15
million btu/year, ie 366.6 kwh worth $36.66 at 10 cents/kwh at 120 f in a
65 f room, adding $7 worth of r19 insulation would lower this to $12.69,
for a net $23.97 savings and a $7/23.97x365.25 = 107 day simple payback.
nick
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