My basement studio/office is not connected to house heating and cooling, but manages to stay comfortable all but 2-3 months of the year. By about January, it’s lost enough heat to be chilly; I use a small spot heater in the office and am fine. By about July, though, it’s a little warm and more humid than I’d like. So I am considering a portable unit to do something about the humidity (90%) and the temperature (10%).
My understanding is that portable AC units and portable dehumidifiers are essentially the same unit, with the difference being that the heat from the AC’s condenser is exhausted through a hose (and out a window or other opening) while a DH recycles the air, sending it first through the evaporator and then through the condenser, resulting in very slightly warmed but lowered-humidity output. Is that correct?
Which is more efficient? If I don’t much care about lowering the temperature, would a DH be more power and runtime efficient at drying the air without raising the temp too much? Or are there convertible units that will do both jobs, at least handling de-H’ing well?
I’m curious to hear facts on this, but my guess is that for marginal conditions, a dehumidifier should be sufficient, and considerably cheaper on energy. Your body can cool quite well if the humidity is reasonable and the temperature isn’t extreme, expecially if you’re sedentary rather than active.
If there’s not much air exchange, once the air is dry, it’ll tend to stay fairly dry, assuming the room is reasonably sealed from moisture coming from below. (If not, consider a basement dewatering system). Unlike humidity, temperature can be exchanged by radiation and conduction, so a unit has to run more often to keep a room at a lower temperature.
Plus, dehumidifers are cheaper to buy in the first place. I’d give it a try. But then, I’m kinda cheap.
Dehumidifiers don’t have a big circulation fan, and run on a lower duty cycle. So they’ll cost less to operate, last longer, but won’t do much to change the actual temperature in the room. But drying the air will make the room feel cooler, and if that’s enough it’s a good option. Also, they don’t make any significant noise like a window AC will.
when using a dehumidifier you have to keep the cold coils from freezing. you may need to elevate the unit a number of feet off the floor to get it into warmer air. elevating allows you to drain water through a hose. if you do elevate it it has to be stable, its vibrations will cause it to move.
Why do you have to keep them from freezing, water will still condense on the frozen coils? Is it a matter of efficiency?
the whole coil area will eventually, over an hour or two, become a solid block of ice and block the airflow.
Ok, I get you. What I’m familiar with would cycle in less time than that, but maybe not if it gets humid enough.
never experienced a dehumidifier icing over. That is if it in not low on charge.
I recall my dad battling a home AC unit that tended to freeze over, and one in a rented house that my landlord kept trying to cheap out on fixing. Both were faulty and possibly undercharged. I don’t think any modern refrigeration/chilling unit will freeze over if it’s operating correctly. (That is, if it’s forming ice on the evaporator, there’s something wrong with it - it’s not usage or user error.)
Haven’t had that problem with mine, at normal room temperatures.