It helps to know about the components of you HVAC system to take proper care of the equipment. The hot, humid air in northwest Indiana places a lot of demand on your air conditioner, but your furnace also works hard in cold weather too. Understanding your system and performing annual maintenance could prevent a costly repair and the stress it can cause.
The thermostat controls the operation of your central HVAC system. Simple mechanical thermostats can be set to a particular temperature and will turn on the system as needed to maintain that particular temperature. Programmable thermostats can be programmed to maintain different temperatures for different times of the day and different days of the week automatically.
Most customers are choosing to upgrade to WiFi Thermostats. These give you all the options with access through any computer or hand held device. If the event of a breakdown occurs, the thermostat will notify you through email, helping you better prepare for the situation if away from home.
Furnace / Air Handler
The furnace/air handler is a large appliance that turns fuel or electricity into heat for your home. It's usually installed in the basement, attic or a closet. Gas, oil or another fuel is burned or electricity is drawn to create heat and transfer to air passing through. The warm conditioned air is then blown into the central duct system and out to the living areas.
Every furnace contains a heat exchanger. This component is typically made of stainless steel sheet metal shaped as a plate or tube. When the burners ignite and burn fuel, the heat exchanger heats up. It then transfers this warmth to the air flowing over it.
The heat exchanger is one of the most important components in your home HVAC system and must be kept clean and free of cracks. Compromised heat exchangers could be fatal, and should be shut down immediately.
This is the large component that sits outside your home. It's surrounded by thin aluminum fins that allow for heat transfer and has a grate on top. It contains the compressor which pumps the refrigerant through the system. The heat is from inside is absorbed in the system and rejected outdoors at this unit.
Keeping the coil clean of dirt and debris such as cotton-wood, will help maximize the efficiency and longevity of the appliance. Turning of the power and spraying the unit with a hose is a good way to care for it.
The evaporator coil works with the outdoor condenser, but it's physically attached to the furnace. They are often misunderstood "other half" of a split system. This N-shaped aluminum component sits quietly on the top or side of the furnace or inside the air handler drawing out heat and moisture from the air inside your home.
Cold refrigerant from the outdoor unit enters the coil, making the entire coil cold. The blower fan pulls warm air from your home over the coil. The refrigerant inside absorbs heat as the coil condenses humidity from the air. The air, now cooler and drier, continues down the ducts and to your rooms.
Ducts / Vents
HVAC air ducts are long conduits made of sheet metal, fiberglass or flexduct (plastic over a wire frame). They run through ceilings, walls, the attic, crawl space or basement, and/or garage and carry warm or cool air from the furnace or air conditioner.
The vents are the points where ducts open into individual rooms. These are usually in the walls or floors, but can occasionally be found in ceilings. Supply registers are the small rectangular vents that deliver warm or cool air. It is important they are well sealed and insulated so the conditioned air doesn't escape or mix with unconditioned air.
Return vents, usually square and larger than supply registers, draw room air back into the home HVAC system to be re-conditioned. Since indoor air is already conditioned and close to a comfortable temperature, recirculating it is more efficient than drawing air from outdoors.