The Basics of Heating, Ventilation and Air Conditioning Heating, ventilation, and air conditioning (HVAC) help keep homes and businesses comfortable. It also improves indoor air quality by removing dirt particles, bacteria, viruses and other contaminants. Despite its well-known impact on infection rates in hospital wards, few standards exist for the design and maintenance of HVAC Tbyrd’s systems in critical care settings. The Surviving Sepsis Campaign recommends introducing an HVAC standard in the ICUs to reduce nosocomial pneumonia incidence. Evaporator Coil While it may seem like a small part of your air conditioning system, the evaporator coil is actually responsible for most of the cooling work in your home. The coil is built into the furnace compartment of your home or attached to it, depending on the kind of air conditioner you have. When the blower fan draws warm air over the evaporator coil, the refrigerant inside absorbs the heat and moisture from the household air. The refrigerant then reaches its low boiling point, and it vaporizes. This carries the heat away from your home as it travels through tubes to the condenser coil outside. Over time, these coils can become dirty if you use cleaning products, aerosol air fresheners and glues that emit volatile organic compounds (VOCs). These chemicals can cause holes in the copper coil, leading to leaks. A professional technician can repair these problems, but it is much better to prevent them with a regular maintenance program. Condenser Coil A condenser coil is a heat exchanger used in air conditioning systems to cool the home. Like the evaporator coil, it uses refrigerant to transfer heat. However, it is located in the outdoor unit of the system instead of the air handler. The compressor draws the refrigerant, which is in a low-pressure gas state, through the condenser coil. The condenser coil is made of large metal fins that increase its surface area. This allows it to reject more heat to the outdoors, making the process more efficient. The condenser coil is typically made of copper or aluminum. Both have good conductivity when transferring heat, but copper is more durable and easier to repair. A dirty or damaged condenser coil will cause the system to consume more energy than necessary, which can lead to poor cooling performance and shortened system life. In order to prevent a problem, it is recommended that the condenser coil be cleaned regularly by an experienced Frigidaire contractor. Fan The fan setting on your thermostat controls the blower to circulate hot or cold air through your home until the temperature set on the thermostat is reached. The fan setting can also be turned on manually so that the system blower stays running to help with indoor air quality and to clear dust from the system. Some fans are specially designed to filter your home’s air. They can significantly reduce allergens in the house and may help ease allergy symptoms. Thermostat A thermostat is the direct line of communication between your home and your HVAC system. It prompts the system to start running when the air gets cold, then turns off when it warms back up. It is important to keep your thermostat working properly. A malfunctioning one can cause your home to run too much, leading to a high energy bill and a shorter lifespan for your unit. Thermostats can be mechanical, electrical, or even smart. Smart thermostats are wi-fi programmable through an app on your phone and can monitor local weather forecasts. However, they require more upfront investment and may be less reliable than other types of thermostats. Older mechanical thermostats use a bi-metallic strip that coils and uncoils based on temperature to trigger the heating system when it’s needed. Modern thermostats work on a similar principle, but respond much more quickly thanks to their circuitry. Thermostat wiring runs on low-voltage power and is safe to work on, but the circuit feeding it should always be shut off before beginning any repairs or alterations.