Catching things going on with your air conditioner sooner rather than later is the best way for you to keep small issues small and prevent them from turning into big issues. When your air conditioner starts to have something going on with it, there will likely be signs, but they won't always be big ones. This is why you want to learn about the different things, both obvious and less-obvious, that can happen when the air is having problems.
The air is warm - If warm air comes out of your registers, then there are a few different things that can be causing this. Some of these include:
The thermostat may have been switched to the 'on' rather than being on 'auto'
The air filter is clogged from too much dirt and it needs to be replaced
The unit is frozen
The refrigerant is low
There is a leak in the system
There is a problem with the compressor
The air conditioner cycles too often - You likely know about when the air conditioner is going to come on again. This is because the system will have a relatively routine schedule with regards to when it comes on. However, the air conditioner can end up coming on too often if there are certain things wrong with the system. The system may just need to be tuned-up, but the problem can also be something more serious that they will have to repair. So, if you notice that your air conditioner is coming on more often than what you think it should, then you want someone out to take a look.
Your house is too humid - You can find yourself suffering through plenty of humid days once spring and summer come around, but you can usually find relief from that humidity once you step inside your house. If you find the house is still as humid as the outside is, then you should call a tech out. Your HVAC system should take care of a lot of that humidity and if it isn't, then there is likely something wrong with it that needs attention.
You have leaks in the home - There are two types of fluids that you may end up finding in your home from your air conditioner. The AC uses refrigerant to cool your home and water will come in the form of condensation. However, either of them should end up inside of your home and if they do, then someone needs to come out to fix the problem that is causing the issue. Seak out professional air conditioning repair services.