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Dave Martindale Dave Martindale is offline
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Default Can portable radiators be repaired?

Tony Hwang writes:

You still believe that 2 different 1500 watt heaters can have a
difference in efficency, that 1500 watts is not 1500 watts.Think
again.


Of course. Depending on that 1500W rating is outpt or input.
If input.... different heating element will put out different
output. Difference in enniciency.


If the elements are different in efficiency, where does the rest of the
energy go?

In a motor, efficiency is the ratio of shaft mechanical power out to
electical power in. The difference is energy that is wasted - almost
all of it as heat. But in a heater, heat is the *desired* output, and
resistors are 100% efficient at converting electricity to heat - no
matter how the resistor is made.

A heater with a fan uses a small amount of input energy for the motor
instead of directly converting it to heat. But even that is eventually
converted to heat - some in the motor windings, some in air turbulence.
All the energy ends up as heat.

Dave