The purpose of this document is to assist those who may want
to add a window air-conditioning unit in their off-campus unit. This is not permitted where Caltech has
provided air-conditioning. Caltech
sells only casement style a/c units for use in the on campus dormitories. We sell no other a/c units. Prior to your purchase of any air conditioning
unit, you must call Housing Maintenance at 626-395-6175 and have them site
inspect to ensure you have the electrical power needed to operate a window a/c. If it is determined that the electrical
service cannot handle the additional load of adding an air conditioner, Caltech
will make no changes in order to accommodate an air conditioner.
If you are able to install an air conditioner, Caltech must
install it. You will be charged the exact
labor rate for installation. The
average labor cost for this installation is $45.00. The average labor rate per hour per man is $30.00.
Here are some helpful hints on purchasing a window
air-conditioning unit for use in an off campus unit.
The window unit is (usually) easy to install into any standard double-hung
window. It should offer multiple cooling options (low - high). This is the kind
that most people get because it's the cheapest.
Weight: approximately 120 lbs.
Before you get ready to
go shopping, it's a good idea to check out Consumer
Reports or some other product-rating publication so you know which
models are recommended based on what you're considering buying. Don't select a
no-name brand without researching it or you won't know what kind of quality and
durability you're getting. If you aren't interested in hunting down air conditioner
brand ratings, then pick a brand you already trust, such as General Electric,
Amana, Sharp, or Whirlpool.
Now you're ready to go to
the store. To find one, we suggest that you look in your newspaper for air
conditioners that are on sale and see what else they have in stock. We also
recommend that you go to a "superstore" that specializes in selling
appliances such as air conditioners (they tend to have the best people on staff
to help you… in fact, they're super). And most importantly, don't forget to
bring your room dimensions along with you.
Btus and EERs
Once you arrive at the
store, the first thing you should look at are the air conditioner's Btus and
- Watch your Btus. The first thing you're
going to come across when you go a/c shopping is the term
"Btus." Here's what it means: every air conditioner has a
cooling capacity number that ranges from 5,000 to 18,000 Btus. The higher
the Btu value, the stronger the air conditioner is. (For the people out
there interested in such things, "Btu" stands for "British
"Oh, then I should get an air conditioner with the most Btus
possible, right?" NO. Believe it or not, it is possible for an
air conditioner to be too powerful (even on its lowest setting).
Furthermore, the more Btus an a/c has, the more it costs. Btus are the
best indicator of what air conditioner you should buy, so carefully figure
out what you're looking for. The smaller the room, the fewer Btus needed.
There are two methods to figuring out how many Btus you need:
- Find the square footage of the room (multiply
its length and width). Then check out this chart to see where
- Find the square footage of
the room, and multiply the answer by 35. That'll get you in the right
Here's an example: Let's say your apartment is 12' x 15'. So that's 180 square
feet. Using method (1), you know that you should be looking for an air
conditioner in the low 6,000 Btus. Using method (2), you are recommended to get
an air conditioner with about 6,300 Btus (180 X 35).
In addition, you should follow the following guidelines for proper selection:
- If the room is shaded,
reduce the Btus by 10%.
- If the room is very sunny,
increase the Btus by 10%.
- If you plan on placing the
air conditioning unit in your kitchen, add 4,000 Btus.
- If more than two people will regularly be in
the room (e.g., an office), add 600 Btus per person.
- Find the EER number for each unit. "EER" stands for
"Energy Efficiency Ratio." Air conditioners with high EERs are
good, because they cost less to operate. Unfortunately, they're also more
expensive, so you have to find a balance. Air conditioners' EERs usually
range from 8.2 to 10.5. So if you're going to have your air conditioner on
24/7 and you're planning on keeping it for a couple of years, then it's
worthwhile to get an a/c with a high EER. If you only need an air
conditioner to last you through the summer (and you're planning on being
at the beach most of the time anyway), get an air conditioner with a low
Here are some other things to think about when purchasing
your air conditioner:
- Warranty: Perhaps the most important feature of all,
particularly if you have a history of bad luck with electronics. Be sure
that your air conditioner comes with at least a one-year warranty that
covers labor and parts on the entire unit. This way, if something breaks
down, you can return it and get a new one or send it in to be serviced
free of charge. Some stores even offer an extended warranty plan (typically
covering four to five years instead of just one) for an extra fee. This
may be a smart purchase if your electronics always seem to break right
after the one-year mark.
- Temperature range: If it spans less than 20°
(e.g. 68°-86°F), it may not be sufficient for your needs, particularly if
you live in a hot, arid climate.
- Temperature increments: Be sure that the
temperature can be incremented in notches of 1°-2°. This allows for
greater precision and prevents electricity waste. If you have the cash,
get an air conditioner with a digital system (as opposed to a dial),
because it allows greater precision.
- Sleep setting/Energy saver switch: Some unit air conditioners
have a sleep setting so that at night when you are sleeping, the air conditioner
slows the cooling process to a minimum, saving money and energy.
- Slide-out filter: Every unit air conditioner
has a filter that must be cleaned. Save yourself an immense hassle and get
a slide-out filter air conditioner, not a frame-enclosed one. The
slide-out filters are easy to remove and re-install.
- Fan speed settings: How many fan speeds are
offered on the unit? The more settings available, the better the energy
saving will be (and the more choices you have).
- Installation: Make sure your unit air conditioner comes
with installation directions. There's nothing worse than getting the thing
home and suddenly realizing you have no idea what you should do with it.
If you have any questions about the installation process, definitely ask a
store employee for advice before you leave and attempt it yourself. Some
air conditioners require that you drill holes into walls or bricks. It would be nice to be aware of such things in advance.