Heat Pumps
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It's not hearth related so there is not too much except as far as their energy efficiency goes. Your post has been moved to the green room where most of the heat pump discussion has taken place.
Thanks for the response. My question is ... is it more cost effective to run a Fujitsu Heat Pump on automatic or for example, when air conditioning is needed, should one leave it just on the "cool" mode / and would this apply as well for the "heat" mode. Please type very slowly for me to understand. Thanks!
I'm no expert, but I would guess that 'automatic' allows the unit to switch between heating and cooling without user input. Such systems usually have what is called a 'deadband', a few degrees difference between the temperatures where the AC kicks on (warm) and the heat kicks on (cool).
IF the deadband were too small, you can have a situation where the system would cool for a while, then decide it was too cold and heat for awhile, then decide it was too warm and cool for awhile, etc. In other words, it could run all the time when the weather was mild outside == a big waste.
That said, the engineers at Fujitsu presumably made the deadband built into your unit large enough to avoid that wasteful outcome. The problem is that for some folks, the deadband is larger than the comfort band for people. In 'auto', you might get a little warm before the AC comes on, or a little cold before the heat comes on, or both.
At any rate, I think you should not worry about this issue at all. When its really hot or really cold (when you are using the most energy/electricity), there will be no real difference between the efficiency of its operation on auto or not (assuming you maintain the same indoor temp). In those cases it is just running the same way as if it were set to heat or cool. The auto setting will only really be useful/needed in the spring and fall when your weather is hot during the day and cold at night, when your energy/bills are not likely to be very significant.
I, and most people, like to just open our windows during that time of year anyways when it is 'nice' outside.
Bottom line: the 'auto' setting is not that useful for most folks, unless you maybe lived in a desert (large temp swings) in a poorly insulated house (so the temp inside followed the outside) or no one was home most of the time (to open/close windows at appropriate times).
IF the deadband were too small, you can have a situation where the system would cool for a while, then decide it was too cold and heat for awhile, then decide it was too warm and cool for awhile, etc. In other words, it could run all the time when the weather was mild outside == a big waste.
That said, the engineers at Fujitsu presumably made the deadband built into your unit large enough to avoid that wasteful outcome. The problem is that for some folks, the deadband is larger than the comfort band for people. In 'auto', you might get a little warm before the AC comes on, or a little cold before the heat comes on, or both.
At any rate, I think you should not worry about this issue at all. When its really hot or really cold (when you are using the most energy/electricity), there will be no real difference between the efficiency of its operation on auto or not (assuming you maintain the same indoor temp). In those cases it is just running the same way as if it were set to heat or cool. The auto setting will only really be useful/needed in the spring and fall when your weather is hot during the day and cold at night, when your energy/bills are not likely to be very significant.
I, and most people, like to just open our windows during that time of year anyways when it is 'nice' outside.
Bottom line: the 'auto' setting is not that useful for most folks, unless you maybe lived in a desert (large temp swings) in a poorly insulated house (so the temp inside followed the outside) or no one was home most of the time (to open/close windows at appropriate times).
Thank you muchly for this excellent piece of information and advice. I think your answer has pretty well summed up this whole issue. Thank you so much again
If you are doing wintertime heating, its best to let the unit run continuously rather than cycling it. Heat pumps don't put out Hot air, they put our warm air. It takes a lot of heat to bring a space back up to temperature if you cycle the unit, you are far better just running with a lower fan speed.
Right now, I'm doing 90% air conditioning. At nights, it does cool off a bit and I have switched from air conditioning to heat. It was then that I was considering the automatic thing but wasn't sure if I was doing the right thing economically speaking. Appreciate the feedback
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