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Fujitsu Slim Duct system with AirCycler?

MattJF | Posted in General Questions on

I am wondering if anyone familiar with the ARU9RLF/ARU12RLF/ ARU18RLF sees a way to turn on the indoor unit fan only using an external device like an AirCycler.

My thought is that this may be a cost effective method of providing well distributed ventilation. The extensive modulation of these units should make this method more efficient than a traditional furnace installation because the unit will be running much more often. There are likely times when the unit will still need to be forced on though. Supplying concentrated hot/cold air directly to the unit should also give a small efficiency boost vs first diluting it in rooms.

Here is the documentation I have found:

I don’t see an obvious way to turn on only the fan with the input board. There is a fresh air output, just no input that I see. I am hoping this doesn’t require too much creativity.

On the creative front something might be able to be wired into an extra remote (which has a fan button) or directly on the inside unit power PCB.

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  1. user-626934 | | #1

    Not possible, as far as I know. That said, the air handler fan runs most of the time at one speed or another, unless the thermostat is off. You could still hook up an Air Cycler timer/damper if you can provide separate power for it.

    Warning, if you actually want some real ventilation airflow, don't use an Air Cycler system. They require a relatively high return-side static pressure design/install in order to actually move significant airflow.

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