AC window unit a problem?

[Jeffrey A Hayes]

Hi BP.

I’m looking at several great duplexes and one thing that seems to be a sure thing. They all have window units. I know it’s probably the only thing that makes sense from a tenant billing perspective.

Look forward to your input.

[Matt R.]

A window unit will blow cold air just like a central A/C will.  :)

From what I've seen, a single window unit works pretty well on smaller units, like studio or 1-bedroom apartments.  Once the units get bigger, you may need something like one window unit per bedroom; people don't always want to leave all the doors open so one unit can cool the whole place.

If there is more than one window unit per unit, and one of them craps out, you usually have the option of shuffling a working one into the bedroom(s) and then getting a new window unit tomorrow.  In the summer, Wal-Mart (24 hours a day) usually has some in stock; I'm not sure if they stock them all year, though.

You do have to clean the filters on them.  Often this isn't a paper throwaway filter like a central A/C has, but a section of wire or plastic mesh in the front grille that you can pull out and wash.  You might consider buying spare filters, so when you go for a maintenance visit, you can just swap in a clean one and take the old one back with you to wash later.

They should tilt towards the outside of the house a little bit, so the condensation drips out the back.  Normally this happens "automatically" when they are mounted in the window, but it's a good thing to check every couple of years, so they don't start dripping inside the house.

If the unit ends up dripping somewhere you don't want it to, some units have a place you can connect a drain pipe/hose and move the drip over a few feet.  You don't usually plumb this into a drain; you just use a few feet of pipe or hose to get the drip away from the doorway or whatever.

If the unit has more than one bedroom, it's kind of common for the outlets in two of the bedrooms to be on the same circuit.  Two window units on one circuit will usually be OK, but it doesn't leave a lot of room for the tenants' stuff.  You can usually run a few lamps, alarm clocks, phone chargers, etc no problem, but if the tenant wants to (say) use a hair dryer in the bedroom, they might end up popping a breaker.

One disadvantage to a window unit, especially if it's on the first floor in a less-than-great neighborhood, is that it's relatively easy for the bad guys to push it into the house from the outside, and then climb in through the resulting hole.  Most bad guys aren't bold enough to try this when someone is home, but I've heard of it happening when the tenants were away, or when the unit was vacant between tenants.