There are three aspects in a HVAC project that a home owner needs to address when a contractor recommends a new HVAC system for your home. These major areas are design, installation and commissioning. A failure of the contractor to do any of these tasks correctly will have an adverse effect the overall performance of your system.

Design

Selecting the type of equipment that is compatible with the architecture of your home is very important. Zoning systems, the space available for equipment, condition of duct runs, appearance concerns, and project cost must be considered. You should also consider the increased cost of buying higher efficiency (SEER) units with the potential savings and return on investment.

A residential heat load, also known as a Manual J, must be completed for each room and for the heat load on each zone. This analysis determines the size of the equipment to be installed. The use of the manufacturer’s blower data, Manual J heat loads and duct system design, also known as Manual D, insures that the duct system will deliver enough cooling to each room.

Installation

A contractor is required to have a license in the State of Texas. It is important to ask the contractor for their license number. Verify that the contractor is a member of the Air Conditioning Contractors of America. ACCA members have access to the latest technical information regarding HVAC systems. ACCA contractors learn how to make quality an integral part of their company operations. The contractor should also carry liability insurance as required by the State of Texas and workers compensation insurance to protect you the homeowner. Permits should be pulled if required by your local jurisdiction. If no permit is required, the job should be completed to current uniform mechanical code standards. This protects the homeowner from failing an inspection should the home become offered for sale. The following includes the major components of an HVAC installation:

• Installing the indoor and outdoor equipment. Split systems are preferred because they offer better installation options.
• Repairing or replacing supply air and returns air ducts. Ducts must be sealed and insulated to R-6 or R-8 if in unconditioned space.
• Installing zoning or thermostat control systems.
• Installing new primary and secondary condensate lines.
• Installing furnace gas piping and venting.

Commissioning

Commissioning is system startup and installation checks. These are the major steps:

• Checking all control cycles.
• Verify that the refrigerant charge meets manufacturer subcool/superheat ranges.
• Checking all power supplies, connections, and vents.
• Measuring and adjusting air flow at the unit and at the rooms to insure proper balance.
• Educating the homeowner about the system and equipment and providing all instructions and manufacturer's documents.

If all these steps are completed and performed correctly you will avoid costly mistakes when purchasing a new unit.

Regards,
Total Comfort A/C Systems
www.tcacs.com

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