Starting with a search on the Type of air conditioner (centeral ac, portable, window, split) and the reasons they break would help you to take a step in the right direction when it comes to getting things from broken to fixed within your home. However, you may not be someone that is aware of the differences within these systems and how to tell if you are dealing with one or the other. While people typically know the type of system they are relying on in their own space, this becomes more difficult if you have recently moved to a new property.
Also, you may be attempting to fix a problem that a friend is having with their system, if this is the case, you should not be expected to quickly be able to know what exactly they are relying on in order to keep their space cool. There are also many property managers that are tasked with the responsibility of caring for property that others are living with. These professionals may not have the time or resources needed to stay current on the technology that is in place in every specific unit that they are currently dealing with. A portable unit is generally used in order to cool a smaller space, it can still weigh about fifty pounds and connect to the window as a source of ventilation that is needed to order to get air throughout the unit. This item takes up a considerable amount of space and can be left within the corner of a room. If it is not turning on, you may want to check the power in order to make sure that things are working correctly.
When you have this type of machine providing cool air to the space, you do not want to hook up anything else in the outlet that it is using to draw power from. If you currently have something hooked up, you should unplug it and begin to see if this resolves the issue that you are experiencing at the moment. If you still are having problems with the air, you should pull out the filer that you are going to find on the side of the unit and simply make sure that it is clean. When you do this, you should be able to overcome the issue and get things back to working as you expect for them to. If you have a central ac unit, the most common problem could be clogging that is caused by buildup over time. Unscrewing the face of the unit and cleaning the inside with air pressure may be the best way to free things up with minimal effort on your part. In the event that you still have this issue, you may want to think about calling out an expert for help. You should also look for freezing when it comes to window units that you may use during the summer months. Calling an expert and getting them to provide service would be the way to go.