A/C checks  - Timing is everything!
Don't be in a rush to get your a/c checked for the season.  Here's why:

The whole purpose of checking your air conditioner is to make sure it performs as well as possible
during those dreaded hot summer months.  One of the biggest keys to a well performing system is
a proper refrigerant charge.  Refrigerant is a very dynamic compound that changes based on
temperature.  If it's cold outside, the refrigerant isn't doing any work or moving any heat.  It's
important to wait until it's at least 70 degrees or above to build an accurate picture of what your air
conditioner is doing.

To illustrate:

When you go to buy a car, you want to see what kind of power the engine has.  So do you jack up
the wheels and pull it into drive to make sure they spin?  Or do you hit the highway to see what the
car can do under a load?  
Everybody wants to hit the accelerator on the highway first!
The same thing is true with refrigerant.  
Refrigerant simply moves heat from inside your
home to the outside unit.  An air conditioner
doesn't create cold air.  If there isn't much heat to
move, it isn't doing any work (like jacking the car
up).  It needs to be warm to see how the unit is
going to perform.
It's best to wait until its warm

Even though you may be anxious to have your a/c checked for the season, wait until it's warm.  This
will help you get the most out of your money and service visit.  Many heating and cooling businesses
will do it early because they are slow with work or they feel they can pressure you into a new system.

Don't forget - Gibson's Repair is a program ally with Ameren's Act On Energy program.  This
program can pays some of the bill if applicable to replace your existing system with high efficiency