Although air conditioners are the best option when you need to cool an entire house or building, wall AC units are one of the better options when all you need to cool is one room. When you're in a building with no central AC, you'll probably have to choose between these units or the window-mounted AC units.
Wall AC units are installed through the wall of the building, and this can create a few complications when it's time to repair the unit.
Unplug the Unit First
The universal rule that you should unplug an electrical appliance before you work on it applies to AC units as well. Unless there is a need to have the unit plugged in, e.g., to check if a certain part is working, any other work you do on the AC should be carried out with the unit unplugged.
When an appliance is plugged in, all electrical components inside it may give you a nasty shock. Sometimes, even touching the external body of the unit may be dangerous.
Take the Unit Down from the Wall
Some people would wish to avoid the inconvenience of taking down the AC unit from the wall and putting it back in. These units can be tougher to install and take down compared to window-mounted units. However, working on the AC from this position may be impractical. If you need to open up the unit and inspect the inside or replace something, doing this while the unit is still mounted will be a serious challenge. When the unit is on the floor, you'll have better access to everything.
Choose the Right Day
As stated earlier, wall AC units are installed in the wall of the building. This means that when you take the unit down to repair it, you'll be left with a hole in your wall. Needless to say, this is hardly ideal, especially if the weather is wet and windy. Pick a sunny day to work on your AC or find a suitable cover for the hole in the wall.
Call in the Experts
As admirable as it may be to try and fix your AC all on your own, you should know when you're beyond your depth. AC problems can be quite difficult to deal with. Calling an AC repair person to handle the more serious issues can save you a lot of time and money. It may also be safer for you.