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What is most energy efficient run-time and/or thermostat differential setting?

What is most energy efficient run-time and/or thermostat differential setting?

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  #1  
Old 08-01-13, 08:12 AM
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What is most energy efficient run-time and/or thermostat differential setting?

West Central Florida; Goodman split a/c (heat pump)

My thermostat allows a differential setting of one to three degrees(I think) which sort of allows me to adjust the cycle times and on some days give the unit a better chance to drop the humidity level(it seems). I've read that longer run times are preferable, but I'm not sure how far this should be taken, if at all. At a 2 degree differential setting from the set temp, the unit can be off from a 1/2 hour to an hour until the unit restarts and then run for 1/2 hour to an hour and 15 minutes or so.

The questions are: Is this advisable?

Is this more energy efficient compared to having a lower differential setting such as the default setting of 1 degree where the unit cycles on and off more often?

Thank you
 
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Old 08-01-13, 10:04 AM
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It won't make that much difference. should spend your time on home insulation, and also make sure the system is at the top notch condition.
 
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Old 08-01-13, 10:43 PM
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A greater differential reduces energy consumption since it takes 10+ minutes of runtime for a system to reach full capacity/efficiency.
 
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Old 08-05-13, 11:49 AM
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For best efficiency & lowering humidity I'd use 2, or possibly 3 in milder weather to try to keep humidity at or below 50% RH.

A lot depends on whether it is windy or calm & how high .9-ACH or low .375-ACH air-infiltration is; as to whether the humidity will rise too much during the longer off-cycle time.

When controlling humidity. always Set the Room TH to AUTO, so the indoor blower cycles off with the A/C.
 
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Old 08-10-13, 11:10 AM
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Thank you for the responses.

I was wondering; is there any rule of thumb to suggest what the on-off surge equals in continuous run time? In other words, since the longer run time is a more efficient use of the electricity, is there a general amount of run time that equates to the additional electricity that would have been used during the on/off cycle surge?

Edit: Or is the additional efficiency due mainly to the 10 minutes suggested needed to get the unit to optimal running capacity?
 
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