When considering a HVAC contractor, ask to see documentation that they carry general liability insurance to protect your property as well as workers compensation insurance on their employees. The State of Texas does not require employers to carry workers compensation insurance. Lack of adequate insurance could be a major problem for you if someone is injured on your property. An air conditioning contractor should always have these types of insurance and this will save you from a claim against your homeowner's policy in case of an accident.

Choosing a HVAC contractor should include checking with the Texas Department of Licensing and Regulation (TDLR). Be sure that the HVAC contractor's license is current and check if the TDLR has a history of disciplinary actions or complaints published on their website at http://www.license.state.tx.us.

Another source for finding a competent HVAC contractor is the local permits office for your municipality. The municipal inspectors know the HVAC contractors who do good work from the HVAC contractors who do poor work.

As HVAC equipment increases in efficiency and gets more complex this requires more knowledgeable and skilled technicians to service and repair heating and air conditioning equipment. Select an air conditioning company whose technicians are certified and have hands-on experience with your system. Due to rapid advances in the industry technical updates on new air conditioning technology is essential, look for organizations that provide technicians certified by North American Technician Excellence (NATE).

Professional associations are another good way to screen for high quality local heating and A/C service companies. This can have a big influence on the caliber of technician that arrives at your home or business, how well your system works, and your overall experience. Look for organizations that belong to Air Conditioning Contractors of America (ACCA).

Once you identify and contact several HVAC contractors set up an appointment with each of them to visit your home. You should not be charged for this initial appointment. During the meeting the contractor should inspect your existing air conditioner and collect a wide range of information about your home, how many windows and type, which direction they face, and R-value of the insulation. The contractor uses all of this information to calculate the heat load to verify that the existing equipment is correctly sized and proposed equipment is also correctly sized. You should receive a written estimate from each contractor. If one contractor submits a bid that is dramatically different from the other bids ask the contractor to explain the difference.

Some HVAC contractors represent only one line equipment and using these contractors has advantages and disadvantages. On the plus side the contractor has probably gone through specialized training offered by the manufacturer. Should there be any problems with equipment performance you may have additional leverage because you may be able to involve the manufacturer. If you get estimates from contractors that sell other brands make sure they are recommending equivalent equipment.