What does “HVAC” stand for?
The acronym “HVAC” stands for “heating, ventilation, and air conditioning”.
How Do HVAC Systems Work?
- Blower/Air Handler – The blower is located in the air handler and draws in air from the rooms in your home via the air return vents. Blowers are actually referred to as air handlers sometimes but you could think of the blowers as a fan and the air handler as a box that has the fan inside of it. So the return the blower is connected to is strategically placed in your home and depending on the construction of your home they might be on the ceiling, walls, or floors. As a given rule you don’t run returns through concrete so if your house is built on a slab foundation then your return and blower are going to be in a closet or attic.
- Air Return – The air return is connected to the blower and it is mainly referred to as the opening where the air return starts even though the air return is itself a ductwork that routes back to the blower and is also insulated in order to reduce condensation forming. Without insulation, or if the insulation is improperly installed or destroyed, then you can get condensation dripping out of your return vents.
- Filter – In most HVAC systems the filter goes on the opening of the air return with a grate or grill to be held in place. The 1″-2″ filters should be replaced every 1-3 months. There are some systems designed that can be replaced at the blower and accommodate much thicker filters that can get away with being replaced only every year. These much larger filter sets at the blower can also be installed later if you wish. The filter does the job of capturing dust from going into the mechanical unit of the blower and causing problems with electrical components and bearings inside the air handler.
- Ductwork – The opening of the air return uses ducts to carry air to the air handler and also the ductwork carries the cool air (in an AC cycle) back out the vents in the rooms of the home. These ducts are usually sized accordingly for each room, flexible so they can be routed easily in your attic or under your crawlspace, and are insulated to reduce energy loss.
- Condenser – Usually when someone mentions an HVAC system this is the unit they think of because they see it outside. The outdoor unit actually houses the compressor, the unit fan, and the actual condenser. The AC condenser works like the radiator in a car in conjunction with a fan to dump heat from the hot Freon in the lines created by the action of the compressor increasing the pressure of the Freon. This dumping of the heat is what cools the Freon in the lines again. The Freon then gets sent back to the coil in the air handler to let the warm air from the rooms pass through again to cool.
- Compressor – The compressor compresses the Freon to be under high pressure in the condenser. This high pressure creates heat which is dissipated via the cooling fins on the condenser and the fan helping the heat radiate away. This action of heat being dissipated under pressure and then released from that pressure is what causes the cooling action of the Freon. (note, this is also how a refrigerator works)
- Evaporator Coils – The evaporator coils are located in the air handler. These coils look similar to a radiator as well except rather than being used to dump heat, they have the cold Freon in them coming from the Condenser outside and the action of the warm air from inside the home passing over the coils cools the air and in-turn heats the Freon a little before it gets sent back to the Condenser again.
- Exhaust Outlets – Many HVAC systems have a furnace and exhaust outlets that exit out the roof. This allows the poisonous gasses to be safely exited from your home, much like a chimney does for a wood stove.
- Electrical Components – To keep all of these systems functioning properly there are control boards, relays, digital circuits, monitoring circuits, damper controls, and your thermostat.
If you think you have problems with your HVAC or that it might be time for an upgrade to a new unit, give us a call. We’ll evaluate your system and help make recommendations for optimum value. After all, we want to keep you cool all summer long and warm in the winter. Just schedule a visit with one of our technicians to talk about how we can help with your thermostat settings. Would you like to learn more options our techs can help you with? give us a call 704-684-5339