As summer is approaching Australia we all will be again running our air con units.
For the last summer we ran our aircon unit on "dry mode" with a minor spike in energy bill. Site requirements for comfort are mostly humidity reduction (~30-40% drop) and some heat reduction (~2-3c drop).
From high school science I remember if dew point is high, the energy required to pull moisture from the air would be lower than cooling the entire contents of a room. Of course cooling would have a dehumidification effect also. That said, I was talking to a HVAC installer who said running units on "dry mode" as opposed to cooling uses far more energy because the compressor is constantly at work and fan is low. A quick google search suggests that "dry mode" is more efficient as both fan and compressor aren’t working to cool the room, rather they maintain a set-point in humidity. Which is correct? I’m not fussed on either mode as long as energy use is optimised and thermal comfort is achieved (https://en.wikipedia.org/wiki/Humidex). In other words I don’t want to waste money to unnecessarily cool a room, or overly dry it.
October 16, 2019 at 07:16PM
