I am curious whether Aircon takes more current when you set the temperature low vs increase fan speed.

Is there a big difference in energy consumption when you set the temperature to 18 compared to 25? I know the biggest consumption is the compressor.

A 18degC setting with low fan speed might feel similiar to 21deC with medium fan speed. Would the consumption be big?

If wanted to make the room to be cool, rules no.1 prevent cool air to leak outside the room else the compressor will keep on running. So in this case it will utilize more power.

This post has been edited by HonMun: Sep 9 2011, 10:17 AM

Doesn't the compressor keeps running when the A/C is on, unless you turn on eco mode.

Does the compressor run harder when the temp is set lower?

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One of the most inexpensive and effective ways to reduce your air conditioning costs is to adjust your thermostat setting. The savings can be significant when you set your thermostat at 78 degrees Fahrenheit or higher. For each degree you raise your thermostat setting, you reduce seasonal cooling costs by 6 to 8 percent.

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Turn off the air conditioning or set the thermostat up a few degrees when you leave home.
Be sure your air conditioner is not blocked. A free flowing air conditioner operates most efficiently Be sure the return air grill inside your house is not blocked by furniture or other items. Filters should be checked monthly.
When air conditioning is on, keep doors and windows closed Turn off kitchen or bathroom exhaust fans when your air conditioning is operating.
Caulk and weather-strip leaky windows and doors.
Shade your home from direct sunlight. Use shades, drapes, awnings, trees and shrubs to block the hot sun from heating up your home.
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The compressor does not run continuously. That is what the thermostat is for. When it is cold enough, the compressor stops. When it gets warm, the compressor starts again.

No insulation is perfect, so "cold" is lost to the outside. Looked at another way, heat is seeping in. The worse the insulation, the more heat seeps in, the more the compressor has to work, the more electricity is used.

In addition, the bodies of the people inside the room generates heat. More people also cause more electricity to be used.

As far as I know, energy saving compressor don't stop running but at much lower speed, it drain the most electricity when start up and retain its momentum in idle until the next round of pumping. When you switch off, you will notice the compressor gradually reduce its power not like in the past, it stop abruptly and start the same manner.

For my knowledge, the longer u on the aircon, the more electricity it takes

Yea right, you have to say it out loud.