Sometimes a unit will cool sufficiently but can still be in need of maintenance or air conditioning repair. If you see ice build up on or near the appliance at the indoor or outdoor location, if you suspect that the unit is constantly running or if the appliance is constantly cutting on and off, or if the obvious happens, it is just not cooling, you may need major air conditioning maintenance. Do not delay.
Your device may seem to cooling just fine, but it may be about to freeze due to coolant issues or a motor dysfunction. Ice build up on any of the hoses associated with the cooing appliance either at the outdoor unit or inside of your home is a tell tale sign that something is not working right. The good news is that if the appliance is still cooling, and you have just happened onto the ice issue, you have probably caught and prevented a major and costly catastrophe. Maintenance, or maybe a new part or two can likely solve the icing issue before the unit totally breaks down and needs totally replaced.
Even in the hottest heat of the dog days of summer a unit should not constantly run in order to keep a home or an area cool. If you notice that your air conditioner seems to never shut off, even if the thermostat seems to be reading a comparable temperature, you certainly will save money be having the device adjusted as a constantly running unit is sucking up a major percentage of available energy which in turn is driving up your electric bill.
It is also only a matter of time before a device that is behaving in this way will totally break down, so insist on spending the cash now to have a proper maintenance check carried out. It will certainly save you money both on your energy bill and on future repair and replacement bills. The aforementioned can also be true if the device seems to be frequently turning off and on. Again even if the temperature inside your home seems to be desirable, a unit that is working too hard is a unit that is not really working properly, and it should be checked out before something more serious and more costly goes wrong.
Last, and the most obvious, if the air conditioner is blatantly not cooling or is not turning on all at, you are in need of maintenance, repair, or replacement. The good news is that a new unit will immediately make a noticeable impact on the cost of your utilities, and even though the immediate cost of replacement can be steep, the new unit is likely to pay for itself in energy usage in the first season of use.