When it comes to appliance repair, most homeowners only call the repair person out when it altogether stops working. However, air conditioners, like many appliances, don't always just up and break out of the blue. Sure, it may choose the literal hottest day of the year to stop working, but it probably showed a few signs that it was coming first. If an air conditioner shows any of the following signs, even just once, a major breakdown is coming and it needs to be inspected. Even just one instance of any of the following means something is wrong, and as a machine, and air conditioner won't get better without repair.
No Cool Air
This is an obvious one. If there is no cold air coming from the vents, but there is still air coming out, there is something wrong. A complete lack of cold air or taking longer than it used to in order to get cold could mean a problem with the compressor or low Freon levels. Even if your air is on full blast and it is kind of cold but not as cold as it used to be, it still means a problem coming on the horizon.
Lack of Airflow
When the air conditioning kicks on, you can expect a certain whoosh of cold air coming from the vents. You may not notice poor air flow from an air conditioner at first, but typically you will notice when some rooms are getting cold and others are not. When this happens, it can also be a sign of a compressor problem or it can mean a problem in your ducts. Occasionally, this is not an air conditioner issue but instead it can mean that debris has built up in the ducts and needs to be cleaned out.
Most homeowners don't do a visual inspection of their air conditioner. If you engage in regular professional maintenance, a homeowner doesn't really need to. However, if you notice moisture around it and it hasn't been raining, it is a sign of an issue. Moisture around the exterior air conditioner unit could be several things, some serious, others less so. One of the less serious causes is a blocked or broken drainage pipe. This needs to be fixed to prevent rusting and mold growth, but it is not such a detriment. Alternatively, it could be leaking refrigerant, which can be a health risk to humans and pets. This is why if there is moisture, it is best to get it investigated, just in case.
Sounds and Smells
Sometimes the best way to anticipate a broken air conditioner is to use your senses. Certainly never lick it, but instead sometimes you can hear or smell an issue coming. Squealing, grinding, and grating are all signs that something isn't right. In fact, any sound that you haven't heard any time it has kicked on over the years is cause for concern. Alternatively, if you smell something strange around the unit or coming through your ducts, it can mean big problems. Often when wiring insulation has burned out in the unit, you can smell it in your home and it is a dangerous issue.