A home’s HVAC, or heating, ventilation, and air conditioning system is what keeps the building warm in the winter and cool in the summer. Moving the interior air through your central HVAC unit cools or heats it and distributes it evenly throughout the entire building. Here’s more on how the systems work together to keep your home comfortable. Asking “How does HVAC work?” is a great idea- the more you know about your home’s systems the better you are at taking care of it so it lasts as long as possible.

Heating

There are several ways to heat a house. The most popular methods currently employ either heated air or water. In hot air systems, a blower forces air past a burner in your furnace that heats it to a specified temperature, then through supply ducts and out into rooms through registers found in the walls or the floors. Cool air registers and return ducts convey bring air back to the furnace to be heated again and distributed. Because heating the air also dries it out, hot air systems may also feature a humidifier mounted on the furnace to keep humidity levels comfortable.

Furnace heating is provided by natural gas, oil or electricity. All use the British thermal unit  (BTU) to measure their heat output, and contractors use special formulas along with other considerations to calculate the correct capacity when matching an HVAC unit to a home or business.

Hot water systems use a technique that dates back to the mid 19th century- the circulation of hot water from a boiler through a system of pipes. The radiant heat is transferred from the pipes into the air either at baseboard convectors or radiators. The water then circles back to the boiler to be reheated. Older houses have one pipe loop that serves the whole house while newer houses have a system of loops connected to individual thermostats. This allows different areas of the house to be heated and makes the hot water system more efficient.

Another way to both heat and cool the house is the heat pump. Heat pumps are popular in areas of the country with milder climates. During the summer, the heat pump acts like an air conditioner. During the winter, it pulls in heat from the air, the ground or a body of water and uses it to warm the house. The drawback with a heat pump is that supplemental heat is needed when temperatures drop below 35 degrees Fahrenheit.

Air Conditioning

Cooling a home is a bit more complicated and expensive than heating it. In this case, heat is removed from the air inside the house and vented outside. Air conditioners also use BTUs to measure heat removal requirements. The equipment for cooling the air is contained in the same unit as your furnace burner if it’s gas powered so it can use the same blower and ductwork for both cooling and heating. AC systems always have an outdoor part for the purpose of venting the heat out. It usually contains a fan that forces air over coils that contain the heated fluid that absorbed the heat inside the building.

Keep an eye on these things…

Paying attention to your thermostat is always a good idea. It should not be constantly adjusted but should stay at the same temperature for the entire cooling or heating season. Programmable thermostats are popular because you can set and forget them. Vents and registers should not be blocked by furniture or curtains, and the area around your outdoor components should be kept clear of anything that could interfere with air flow.

Heating and cooling units require filters to clean dust out of the air, and these filters need to be changed or cleaned according to the manufacturer’s directions. Fortunately, this is easy for the homeowner to do, or if you have a regular maintenance contract the technician can do it for you.

Of course, there’s a lot more information in answer to questions about how does HVAC work? but now you have a general idea of the basics. Call Thompson and Thompson if you think your HVAC isn’t working properly. We also take care of any and all plumbing problems as well!