Saturday, April 12, 2008

Choosing the type of downlight

For the lighting solution to various places in my house with plaster ceiling, I have chosen to use the 6" cone stainless steel finished reflector housing with PL-C (square base) vertical mounting lampholder base and round open stainless steel trim, using 18 watt energy saving compact fluorescent 2-pins PL-C lamp that emits warm yellowish light.

Here is how it looks like:



The reasons being as follow:

6" downlight - downlight with bigger aperture is brighter. 6" is just nice and 8" will looks too large unless the ceiling is very high. By using 6", less downlights are required to light up the area. My living room just has 4 downlights only, located at each corner of the ceiling.

Stainless steel housing and trim - unlike chrome or other finishing, it will not rust or discoloured.

Vertical mounting position - convenient position easier to install and remove the lamp.

Round shape trim - cost is cheaper than square trim. Also, square trim are normally covered with glass.

Open trim - light is brigher than covered with glass lens. Also, small insects might be trapped inside the downlight with glass lens, and later the downlight will be filled by their dead bodies. Replacing the lamp inside requires to remove the glass lens too.

18 watt energy saving compact fluorescent lamp - 18 watt is just nice for the required brightness. Energy saving compact fluorescent saves 80% of electricity from incandescent bulb with same brightness.

PL-C lamp - easier to install (just push in) and remove (just pull out). It works with ballast that enable its lifespan to be twice as longer than the exposed spiral or U shaped counterparts.

Warm yellowish light - actually its brightness is the same as white light, but we have less glare and better eye comfort with warm yellowish light. It is suitable for long time reading too.


This kind of downlight can be installed with emergency option unit, whereby a small rechargeable battery is hiding on top of the ceiling and connected to the light. In case of electricity blackout, the downlights can still be switched on for a few hours by using the backup power supply from the emergency option unit.

Position your ceiling lights far away from the fan

I learnt about this from my contractor too, but I noticed some of my friends were not aware of this and did not done it right for their house. They are suffering from the flicker effects.

You should position your ceiling lights far away from the ceiling fan. This is because if the fan is close to the lights, when its blades is moving, it will have shadow under the light, causing the room to have a flickering lighting effect, which is irritating and bad to your eyes.

If the room is small and there is a ceiling fan on top, you'd better opt for wall lights instead of installing ceiling lights.

Increasing the efficiency of your air-cond

Increasing the efficiency of your air-cond can save you money in your electricity bills, as well as being good to the world environment too.

Here are the measures that I have taken to increase the efficiency of my air-cond:

1. Ensure the outdoor compressor unit blows the hot air away from your house

Some people made the mistake of hiding the compressor behind a pillar or wall. I almost made the same mistake too, if not my contractor reminded me that this will be bad for the dissipation of hot air blown out from the compressor. There should be no obstacle in front of the compressor unit.

Other than that, some people put the compressor unit close to a window, on a wall forming 90 degree with the window. Some other people just put it under the window (remember, hot air rises). This will make the hot air from the compressor blowing towards the window front. The hot air should be blown away from your house, and best located parallel and on top of your windows.

2. Place the indoor unit close to the outdoor compressor

This will not only save you cost in laying the air-cond hose, which normally charges per feet of installation. It will also make the refrigerant gas travels in shorter distance and faster to reach the indoor unit.

3. Confine the cool air from escaping the room

This is a common sense that most people awares. When using the air-cond, close up all the windows and doors to restrict cool air from escaping.

4. Tint the glass of those big sliding windows

There are tinting films available to install on the windows glass, blocking the heat, infrared and ultraviolet radiation of the sun from entering your house. This is particularly effective if the windows are facing west.

5. Switch on the ceiling fan together with the air-cond

This will tremendously increase the airflow, making the room cool down much more effectively, and in turn the air-cond unit need to work less harder.

6. Wash the air filter of indoor unit regularly

The air filter surface will fill up with dust over time. Take it out and wash it with tap water. Rinse it, dry it, and put it back. If the air filter is blocked by dust, your air-cond need to work much more harder.

The cleaning frequency depends on your usage. If you use the air-cond everyday, should clean the air-filter at least monthly. If you use it occasionally, then can clean it bi-monthly or at most quarterly.

7. Service the air-cond at least every 2-3 years

Servicing the air-cond includes disseminating its indoor and outdoor units, and clean with chemical. This will maintain its cooling efficiency.

8. Install turbine ventilators on your roof top

I seldom need to switch on the air-conds in my house eversince the turbine ventilator system is installed. The neccessity to switch on air-cond only come when the indoor temperature reaches above 30 degree Celcius, which is very rare.

And because the turbine ventilator system can effectively improve the air circulation in the house, it does help to make the air-cond works more efficiently the same way like the ceiling fan does, although the effect is certainly not as much as the ceiling fan.

To learn more about the turbine ventilator system, read my other article here.
To learn more on how to select air-conditioner wisely, read my other article here.

Hint: Click on the "Older Posts" link to continue reading, or click here for a listing of all my past 3 months articles.