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Energy Saver: Air Conditioning
(continued ...) condenser coil is hidden from 'view' to the sun by a stamped weather guard then it is mostly shielded from the sun's short wave infrared radiation. Either way, my policy is to locate the condenser in a shaded location when that is a choice. Place the unit on the north side of the building in the northern hemisphere and the south side in the southern hemisphere. The idea is to use your house as a solar shield. If you're at the equator, consider fabricating a frame and put up a sheet metal 'roof' as a solar heat shield. If the unit is already installed or there is no other choice, install a privacy type fence with spaces for air to move through but excludes light. Space the fence and 'roof' according to rules discussed later in this article.
The next possible energy problem is the flow of air that the condenser fan is moving. Here, more volume is always better. For a given fan it has two components to its performance. One is pressure and the other is volume. The relationship can be charted with pressure as the vertical axis and volume as the horizontal axis. Those fan characteristics follow the form of a curve but for our purposes, you can think of it as a diagonal line rising from right-to-left. As one property increases the other decreases and vice versa. Since we want more volume, we want to reduce restrictions that consume the vertical fan performance component; pressure. This is where the weather shield actually obstructs some of the air flow because it consumes some of the fan's pressure to squeeze through the stamped slots. More pressure is consumed as the air flows across the condenser coil but that is where we are trying to transfer heat. That makes that pressure loss a necessary one.
The condenser coil gets fouled by the very process of the condenser fan running and drawing in dust, dirt, pollen, lawn mower blowing chunks of grass, ...