HVAC

How climate control works

HVAC heating and cooling systems closely regulate humidity and temperature and maintain safe and healthy conditions within a home or building. HVAC equipment not only provides climate control for residential, commercial and industrial buildings, but also makes long distance transportation of food and medicine possible. These systems are commonly used in residential homes because of their quiet running and efficiency.

HVAC systems combine three functions into one system: heating, ventilation and air-conditioning. Depending on the construction and location of your home, you will have one of two systems:

1. Split system. These systems have an outdoor unit called a condenser and an indoor unit called an evaporator coil. The system transports heat from one unit to another. In the summer months, the compressor in the condenser changes gaseous refrigerant into high temperature, high-pressure gas. This gas loses heat as it travels through the outdoor coil and causes the refrigerant to condense into a liquid that flows through copper tubing into the evaporator coil. From here, it expands and absorbs heat from the air in your HVAC ductwork, leaving the cooler air to be distributed through the house or building. As the air cools, it is also dehumidified (the moisture condenses on the outside of the coils) and carried away through a drain. This process is the same in the winter months, but occurs in reverse.
2. Packaged unit. This system combines the condensing unit and evaporator coil into one outdoor unit, but works in the same way.

HVAC Troubleshooting

With the HVAC system (as with any heating and cooling unit), problems can arise that can cause the need for troubleshooting. HVAC troubleshooting is often a simple thing such as a loose wire, a dirty filter, poor duct sealing or improper thermostat settings. It is advisable to call a licensed contractor if the problem seems to involve more than a dirty filter or improper thermostat settings. Most HVAC problems can be prevented with regular maintenance.

To use the HVAC system efficiently and avoid maintenance issues, frequent checks should be done on the system, such as:

1. The air filter should be checked monthly and changed as soon as it looks dirty. A dirty filter slows down airflow; wastes energy and can lead to expensive maintenance and system failure.
2. Maintain the HVAC equipment to prevent problems and cost by having a contractor do annual pre-season checks.
3. Installing programmable thermostats can save $150 or more every year in utility costs.
4. Sealing and insulating HVAC ducts improves the efficiency of the system as much as 20 percent.

A central HVAC system is the most quiet and convenient way to heat and cool your home, and can play a big role in reducing environmental impact. Well-designed HVAC systems use minimal non-renewable energy, minimal air and water pollutant emissions, and avoid chlorofluorocarbons and hydrochlorofluorocarbons that are a major cause of damage to the ozone layer.