Dear Mason,

We do not like to run our central air during the summer.  Too expensive, and the house stays pretty comfortable without it.  While this anti-AC policy works for most of our living space it is posing a problem for our music room which, for the sake of protecting the instruments, is kept closed off from the rest of house.  No AC means that during the summer, this 12x15 room gets stiflingly hot and stuffy, borderline unusable and very bad for the instruments.  We have considered purchasing a portable air conditioner which has the added advantage of dehumidification. But alas, the room has those Anderson casement windows that hinge on the side and crank open, so the window vent kits that come with these units will not work.  Is there another way to vent a portable air conditioner?  Is there another option for spot cooling a room? 

 Tracy B;  Ashland, VA

Welcome back, Tracy! 

Readers, did y'all know that Tracy was one of the very first contributors to AskMason almost a year ago?  Your reappearance is sort-of an anniversary present to me!

I am familiar with portable air conditioners - they are something akin to free-standing versions of the familiar window units from the days of yore.  Similar mechanics, although they stand free inside your room, and the hot air "by-product" is vented to the exterior via a short duct - which duct is typically recommended (and comes with a kit to accommodate) running through a partially-open window.

I don't know any reason why the exhaust duct might not be run through a hole cut in your exterior wall, similar to a dryer vent application.  If the materials provided with the unit do not adapt to "other-than-open-window" application, there are plenty of sheet metal adapters available off-the-shelf at home centers.  Worst case, you could get whatever you might need, fabricated by a local sheet metal shop.

You mention the concern for humidity control.  Portable units typically come with either a condensate pan that needs to be emptied regularly (like a standard portable dehumidifier), or a drain tube.  The latter would save you some regular (probably daily, in this area) footsteps, but you need to watch it to make sure the tube stays clear of debris.

Also, we have talked to some extent on this blog, to assure that air conditioning is RIGHT-sized.  Some will tell you to always oversize your heating and air systems; I disagree!  Especially for the dehumidification to work properly, you would prefer for the unit to run at lower levels, for longer cycle times.  "Short cycling" (constant on-of-on-off inherent in oversized systems) does not allow the unit to do a good job of dehumidification.  Further, I would monitor the humidity levels, for most of these simple units simply "dehumidify" in lieu of truly controlling humidity.  We want to protect your musical instruments by providing constant and proper humidity levels, right?

There are some other options - you might check into mini-split systems.  They are more costly, and fairly "permanent".  Most need to be professionally installed.  If these are not enough downsides for you, I also do not know of any such units less than 9,000 BTUh ratings - which would be oversized for this one room.

I will gladly come out and help with the installation, in exchange for a tour of the instruments and a mini-concert!  Best wishes!

Mason

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