"The DIY methods that you can try out before calling in an HVAC expert are the following: For example, if your air conditioner does not turn on you can check whether the condenser is running. You have to ensure that the unit is properly plugged in and the thermostat is rightly set. You can lower the temperature of the thermostat by 5 to 10 degrees and set it to the cooling mode. You will also have to check whether there is a blown fuse or a tripped circuit breaker. In case your air conditioner is on and the thermostat is set properly and still the air conditioner is not cooling, you might have to check whether the condenser has debris around it. Accumulated debris might block free airflow into the rooms. So it is important that you clear the debris and the next step is to clean the filters. Many a times, dirty filters prevent the air conditioner from cooling a room. Sometimes, the cooling provided by the air conditioners might not be adequate in that case, the problem may lie with the size of your air conditioner. If you have an air conditioner that is too small in size or too big compared to the area it has to cool, the result will not be satisfactory. In addition to improper size, the problem may also be with the charge or a frozen evaporator coil. Even after trying out all the DIY methods, if the problem still persists, you might have to "