Beat The Summer Heat - What Size A/c Should You Buy
By Donald Grummett, Fri Dec 9th

Beat the summer heat - what size A/C do I need

What size air conditioner do I need?

A larger air conditioner will not always provide more cooling.It should be sized for the room area. If properly sized itshould operate long enough to remove moisture from the air. Itis the moisture removed from the room which actually producesthe feeling of cooling. Unfortunately many people in their rushto purchase a window air conditioner buy too large a model.

Too large a unit can actually provide less cooling than asmaller, properly sized unit. This is because with an oversizedair conditioner its run time is too short. Consequently it doesnot remove enough moisture from the room to produce a feeling ofcomfort. If you’re A/C seems to cycle off and then back on everyfew minutes and does a poor job of cooling, it is probablyoversized for the room.

Air conditioners are rated in BTU’s. British Thermal Units are ameasurement of how much heat is being transferred form the roombeing cooled to where the heat is dumped out of doors. This iswhy the cooing coil inside the room is cool to the touch, whilethe part that hangs outside is extremely hot.

A window air conditioner used in the average household room canbe as low as 4000 BTU. While 5000, 6000, and 8000 are the mostcommon sizes purchased.

How do I determine what size A/C I need? Following is a basicsizing chart for calculating the window air conditioner neededfor a room. Calculate the size of the room by multiplying thewidth of the room by the length of the room. Use your room sizeto determine what BTU's are required to cool that particularroom size.

room in sq ft--------room in sq m----------A/C size in BTU's

100–250.................9–23...................5000–6000250–400................23–37...................6000–8500400–550................37–51...................8000–11000550–875................51–811..................1000–15000

Based on a room occupied by two adults, having an averageinsulation, number of windows, and sun exposure.

Which is the best room for placement of an air conditioner?

Wherever it gives the most comfort is where it should beinstalled. If you only have one air conditioner then we usuallysuggest the bedroom. This is because most people find that ifthey can sleep comfortably during a hot summer night then theirnext days work will be a lot easier. Getting through a hot dayat work becomes a lot easier when you know you will sleepcomfortably that night.

Some people do not like a cool sleeping environment so they willtend to place it in a living room or family room. Or some peoplewill place it in the family room because the whole family cansleep there. Get out the sleeping bags and turn it into anadventure for the young ones. Beats waking up in the morning tofind a dog, cat, and four kids in the bed with you.

Also window air conditioner can be noisy, which may disturbsleep. Others find the drone of the fan actually promotes sleepbecause all the neighbourhood noises are drowned out. Somepeople say the air conditioner works as well as a sleeping pill

But whichever room you eventually pick don’t expect theimpossible from you’re A/C. It is not meant to cool more thanone room or one open area. Air conditioners will not cool otherrooms? This is because the blower in a window air conditioner isnot very powerful. It is sized to cool one open area, not anumber of interconnected rooms. Therefore once again a couple ofsmaller units may be better for your home than one large unit.

Lastly, remember to properly secure the air conditioner in thewindow. Once installed a piece of wood to stop the window frombeing lifted up is a good idea. If you have wooden sills thesimple addition of a wood screw at the top of the raised window(the one you had to raise to install the A/C) will only take aminute. Otherwise an intruder could gain access to the house bylifting the window and letting the A/C fall out. This couldresult in the loss of both your valuables and the airconditioner.

About the author:Copyright 2005 by Donald Grummett. All right reserved. Servicemanager of MG Appliance Repair Services in Ottawa, Canada. Inthe trade over 30 years as a technician, business owner, andtechnical trainer. For more information about appliancesincluding FAQ, Stain guide, Recycling, and Newsletter visithttp://www.mgservices.ca