Frequently Asked Questions

1. What type of air conditioners (Aircon) do I need?
Air conditioners come in four main types in Singapore: window units, through the wall units, portable units and whole house/central air units. Window units come in three main flavors: double-hung windows, sliding windows and casement windows.

Window units will usually convert between types with special hardware, which is often included. Small through the wall units will often convert into window units. Large through the wall, and central air units usually require professional installation, which adds to the cost.

2. What features do I need?
You should expect the unit to have an adjustable thermostat, at least two cooling speeds, two fan speeds and an energy efficient setting, which stops the fan when the unit is not cooling. The unit should have an adjustable vent, which allows you to aim the cool air, and an exhaust vent setting allowing fresh air to be introduced from outside. The filter should be easily accessible for removal and cleaning. You want a manufacturer's warrantee for at least 5 years, with full replacement for at least 1 year.

Some of the newer units have an electrostatic filter available either standard or as an option. This filter will remove extremely small particles from the air. This is a superb feature for people with allergies.

3. What is EER?
EER or Energy Efficiency Ratio is a measure of how efficient a particular air conditioning unit is. The higher the number, the more efficient the unit and the less it will cost each year to run. Small units currently have a top EER of about 11, while the most efficient large units have an EER of about 13. Don't be fooled by the ranges shown on the yellow tags. The top rated units are often beyond the range.

4. What cooling capacity do I need?
Cooling capacity is measured in BTU/hour. (British Thermal Units per Hour) The higher the number, the more powerful the unit is. A small room of 150 square feet may only need a 5000 BTU/Hour unit, whereas a room of 1200 square feet may need a 19,000 BTU/Hour monster.

However, room size is not the only factor that contributes to the capacity. There are many other factors including:

· the number and size of the windows
· the direction the room faces
· the available shade
· how well the room is insulated
· how many people use the room
· what appliances (computers etc.) are in the room

It is important to get a unit as close to the correct capacity as possible. Too small a unit may not be able to cool the room on a hot day. Too large a unit will cost more to operate. It may also cool the room too quickly and leave excessive moisture in the air.

5. How do I calculate the payback?
Start with the EER of your old unit. Subtract 1 from this EER for every 5 years of its age -- more if you never clean it. Use the guide to generate the annual cost for the old unit and for the unit you want to buy. You may have to extrapolate if the figures are beyond the range of your chart. Subtract the two numbers to get the annual savings. Divide the purchase price by the annual savings to get the payback time. If the payback time is lower than the warrantee period, it's like money in the bank. If it is less than double the warrantee period, it is still probably a good buy.

6. Which AC should I buy?
You should buy the unit of the correct capacity and type that has the highest EER, if you can afford it. Buying a unit of lower EER that costs less is usually a false economy. However, in areas with very short cooling seasons, or extremely cheap power, a lower cost unit may be a good buy. (Use your guide to find the annual cost to run the two units. Multiply the difference by the length of the warrantee. Add that number to the cost of the lower unit. Is it still a bargain?)

Of course, common sense still applies so follow the normal rules:
· Consult the manufacturer's site for the EER, BTU/Hour and list price.
· Check the manufacturer's site for rebates.

Or call CE Engineering @ 6100-8900 for more information.