Is 100% Efficency on a AC Unit Possible?

Old 07-05-12, 09:09 AM
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Is 100% Efficency on a AC Unit Possible?

Recently, on a regular service call, I came across an AC unit that had an Energy Efficiency sticker that stated the machine was rated at 100% efficient. Don't get me wrong, that would be awesome, but from everything I was taught, 100% efficient for air conditioning is impossible. Is it true that we now have 100% efficient machines, or is this sticker a typo or just lying. Just curious since i have not come across any other machine claiming to be 100% efficient.
Old 07-05-12, 09:12 AM
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My understanding of physics makes 100% efficiency impossible.
Old 07-05-12, 11:49 AM
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Was it powered by a perpetual motion machine and have a zero temperature loss line set?
Old 07-05-12, 12:42 PM
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Ac and heatpump systems move more energy than they consume.

There are 3.4 btus in a watt hour. SEER is BTUs per watt hour of electricity consumed.

Even an older 8 EER (steady state efficiency at 95F outdoor)/ 9 seer (seasonal efficiency) unit removes around 2.3 units of energy for every unit of energy consumed.

Modern 15 SEER / 12 EER systems can remove 3.5-4+ units of energy for every unit of energy consumed.

Seasonal efficiency is higher than steady state efficiency because it's measured at a lower outdoor temp.

The typical compressor motor may be 80% efficient at converting electrical energy to kinetic energy.

Most standard blower motors are only around 60% efficient on the highest speed.

Variable speed / ecm motors are over 80% efficient at all speeds.

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